Connecticut State Line includes the line features of a layer named Connecticut. Connecticut is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut. The State of Connecticut is represented as one polygon feature surrounded by linear boundary features. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994. Connecticut State Polygon includes the polygon features of a layer named Connecticut. Connecticut is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut. The State of Connecticut is represented as one polygon feature surrounded by linear boundary features. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994.

Connecticut and Vicinity County Boundary data are intended for geographic display of state and county boundaries at statewide and regional levels. Use it to map and label counties on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

This CT Full State layer consists of two individual polygons representing the land and Long Island Sound borders that make up the state of Connecticut.

This land portion of this feature layer is directly derived from the 'https://geodata.ct.gov/datasets/CTDOT::ct-municipalities/about' rel='nofollow ugc'>CTDOT Municipalities feature layer geometry, created by CT Department of Transportation. The full state is created by dissolving all the municipalities into one polygon.

The Long Island Sound portion is derived from points defining the Connecticut state waters boundary line, as described in the 'https://portal.ct.gov/-/media/deep/fishing/commercial/marinecircpdf.pdf' rel='nofollow ugc'>CTDEEP Marine Fisheries Information Circular (Table 6).

This feature layer includes US Census Federal Information Processing Standards (FIPS) codes that are associated with the state of Connecticut.

Northeastern United States State Boundary data are intended for geographic display of state boundaries at statewide and regional levels. Use it to map and label states on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

Connecticut and Vicinity Town Boundary data are intended for geographic display of state, county and town (municipal) boundaries at statewide and regional levels. Use it to map and label towns on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

Analysis of ‘CT Vicinity County Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/637d9080-8681-4ce8-8908-a50a9af31c41 on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Connecticut and Vicinity County Boundary data are intended for geographic display of state and county boundaries at statewide and regional levels. Use it to map and label counties on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

--- Original source retains full ownership of the source dataset ---

Connecticut and Vicinity Town Boundary data are intended for geographic display of state, county and town (municipal) boundaries at statewide and regional levels. Use it to map and label towns on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

Analysis of ‘Connecticut Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/4eec1491-21ff-466c-a8c7-024c036ea493 on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Connecticut State Line includes the line features of a layer named Connecticut. Connecticut is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut. The State of Connecticut is represented as one polygon feature surrounded by linear boundary features. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994.

Connecticut State Polygon includes the polygon features of a layer named Connecticut. Connecticut is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut. The State of Connecticut is represented as one polygon feature surrounded by linear boundary features. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994.

--- Original source retains full ownership of the source dataset ---

Connecticut Mainland Line includes the line features of a layer named Connecticut Mainland. Connecticut Mainland is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut with an additional linear shoreline feature separating the Connecticut mainland from the waters of Long Island Sound. The layer includes a polygon feature representing the Connecticut mainland, a polygon feature representing Connecticut waters in Long Island Sound and approximately 700 polygon features representing Connecticut islands in Long Island Sound. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 2005.

Connecticut Mainland Polygon includes the polygon features of a layer named Connecticut Mainland. Connecticut Mainland is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut with an additional linear shoreline feature separating the Connecticut mainland from the waters of Long Island Sound. The layer includes a polygon feature representing the Connecticut mainland, a polygon feature representing Connecticut waters in Long Island Sound and approximately 700 polygon features representing Connecticut islands in Long Island Sound. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 2005.

Analysis of ‘Northeast County Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/e1d6ced4-6bc5-41b6-ae3f-c1b67cb17293 on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Northeastern United States County Boundary data are intended for geographic display of state and county boundaries at statewide and regional levels. Use it to map and label counties on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

--- Original source retains full ownership of the source dataset ---

Analysis of ‘CT Vicinity Town Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/5f096fc3-c22e-44ac-ae71-0bdae202f0de on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Connecticut and Vicinity Town Boundary data are intended for geographic display of state, county and town (municipal) boundaries at statewide and regional levels. Use it to map and label towns on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

--- Original source retains full ownership of the source dataset ---

This CT Counties layer consists of individual polygons representing each of the 8 counties that make up the state of Connecticut.

This feature layer is directly derived from the CTDOT Municipalities feature layer geometry, created by CT Department of Transportation. The municipalities are dissolved into their associated counties.

This feature layer includes US Census Federal Information Processing Standards (FIPS) codes that are associated with each municipality. This was included based on information from 'https://www.census.gov/programs-surveys/geography/technical-documentation/county-changes/2020.html' rel='nofollow ugc'>Connecticut County to County Subdivision Crosswalk from the US Census.

The 9 Planning Regions in Connecticut have replaced the counties for statistical and administrative functions, so these 8 counties are used only in legacy geography.

Connecticut’s 9 planning regions provide a geographic framework within which municipalities can jointly address common interests and coordinate such interests with state plans and programs. CGS Section 16a-4a authorizes the Secretary of the Office of Policy and Management (OPM) to designate or redesignate the boundaries of logical planning regions. CGS Section 4-124j authorizes the member municipalities of each planning region to establish a formal regional governance structure known as a council of governments (COG).

For more information see:

• 'https://portal.ct.gov/opm/igpp/org/planning-regions/planning-regions---overview' rel='nofollow ugc'>CT Office of Policy and Management, Regional Councils of Governments in Connecticut
• 'https://www2.census.gov/geo/pdfs/reference/ct_county_equiv_change.pdf' rel='nofollow ugc'>Final Change to County Equivalents in Connecticut [PDF]
• 'https://www.federalregister.gov/documents/2022/06/06/2022-12063/change-to-county-equivalents-in-the-state-of-connecticut' rel='nofollow ugc'>Final Federal Register Notice
• 'https://portal.ct.gov/sots/register-manual/section-vii/regional-councils-of-governments' rel='nofollow ugc'>CT Office of the Secretary of the State, Regional Councils of Governments

CT Municipalities

CT Counties

CT Councils of Governments

CT Planning Regions

Northeastern United States Town Boundary data are intended for geographic display of state, county and town (municipal) boundaries at statewide and regional levels. Use it to map and label towns on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Edge refers to the linear topological primitives that make up MTDB. The All Lines Shapefile contains linear features such as roads, railroads, and hydrography. Additional attribute data associated with the linear features found in the All Lines Shapefile are available in relationship (.dbf) files that users must download separately. The All Lines Shapefile contains the geometry and attributes of each topological primitive edge. Each edge has a unique TIGER/Line identifier (TLID) value.

Analysis of ‘Connecticut Mainland Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/c0cdc025-4b1d-4a8d-ac71-c620422bf7da on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Connecticut Mainland Line includes the line features of a layer named Connecticut Mainland. Connecticut Mainland is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut with an additional linear shoreline feature separating the Connecticut mainland from the waters of Long Island Sound. The layer includes a polygon feature representing the Connecticut mainland, a polygon feature representing Connecticut waters in Long Island Sound and approximately 700 polygon features representing Connecticut islands in Long Island Sound. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 2005.

Connecticut Mainland Polygon includes the polygon features of a layer named Connecticut Mainland. Connecticut Mainland is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut with an additional linear shoreline feature separating the Connecticut mainland from the waters of Long Island Sound. The layer includes a polygon feature representing the Connecticut mainland, a polygon feature representing Connecticut waters in Long Island Sound and approximately 700 polygon features representing Connecticut islands in Long Island Sound. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 2005.

--- Original source retains full ownership of the source dataset ---

Analysis of ‘Town Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/e3a21192-ce30-40a7-8c18-7c8e4459646a on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Connecticut Town Line includes the line features of a layer named Town. Town is a 1:24,000-scale, polygon and line feature-based layer that includes state, county and town (municipal) boundary features depicted on the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps for the State of Connecticut. This layer only includes information for Connecticut. Line features include State, county, and town (municipal) boundaries. Polygon features depict the geographic areas for individual towns (municipalities). A town may be represented by more than one polygon feature. For example, in addition to representing the portion of a town on the mainland, a polygon feature may also define an island along the coast of Long Island Sound. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Attribute information is comprised of codes to classify and cartographically symbolize political boundaries by type and identify the geographic areas encompassed by individual towns. Polygon feature attributes include state, county, and town codes and names. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994. With the exception of the Middletown-Portand town boundary, the 2005 edition, includes the same features originally published in 1994. The Middletown-Portand was corrected and changed from its location, as depicted on the USGS topographic quadrangle maps, from along the banks of the Connecticut River in Portand to the middle of the Connecticut River south of Wilcox Island to the Pecausett Meadows area in Portland. Some attribute information has been slightly modified and made easier to use.

Connecticut Town Polygon includes the polygon features of a layer named Town. Town is a 1:24,000-scale, polygon and line feature-based layer that includes state, county and town (municipal) boundary features depicted on the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps for the State of Connecticut. This layer only includes information for Connecticut. Line features include State, county, and town (municipal) boundaries. Polygon features depict the geographic areas for individual towns (municipalities). A town may be represented by more than one polygon feature. For example, in addition to representing the portion of a town on the mainland, a polygon feature may also define an island along the coast of Long Island Sound. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Attribute information is comprised of codes to classify and cartographically symbolize political boundaries by type and identify the geographic areas encompassed by individual towns. Polygon feature attributes include state, county, and town codes and names. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994. With the exception of the Middletown-Portand town boundary, the 2005 edition, includes the same features originally published in 1994. The Middletown-Portand was corrected and changed from its location, as depicted on the USGS topographic quadrangle maps, from along the banks of the Connecticut River in Portand to the middle of the Connecticut River south of Wilcox Island to the Pecausett Meadows area in Portland. Some attribute information has been slightly modified and made easier to use.

--- Original source retains full ownership of the source dataset ---

Northeastern United States County Boundary data are intended for geographic display of state and county boundaries at statewide and regional levels. Use it to map and label counties on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

Analysis of ‘Northeast Town Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/4bb4327b-4f63-4c70-a83d-68997939d658 on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Northeastern United States Town Boundary data are intended for geographic display of state, county and town (municipal) boundaries at statewide and regional levels. Use it to map and label towns on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

--- Original source retains full ownership of the source dataset ---

Analysis of ‘Northeast Town Lines’ provided by Analyst-2 (analyst-2.ai), based on source dataset retrieved from https://catalog.data.gov/dataset/14ef2805-9546-4018-a421-62880af37b07 on 27 January 2022.

--- Dataset description provided by original source is as follows ---

Northeastern United States Town Boundary data are intended for geographic display of state, county and town (municipal) boundaries at statewide and regional levels. Use it to map and label towns on a map. These data are derived from Northeastern United States Political Boundary Master layer. This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

--- Original source retains full ownership of the source dataset ---

Connecticut Historic Shoreline Wetlands: 1880s NOS T-Sheet Shoreline Features is a 1:10,000-scale, line feature-based layer that includes information depicting historic shoreline features and wetland boundaries for areas of coastal Connecticut during the 1880s. The layer depicts information found on topographic survey sheets (T-sheets) from the US Coast and Geodetic Survey (USC&GS), a predecessor to the National Ocean Service (NOS). The layer represents conditions at a particular point in time. The layer does not depict current conditions. The layer includes ground condition features such as approximate shoreline, shoreline, wetland shoreline, wetland upland boundaries, wetland interior boundaries, man-made shoreline, jetties/breakwaters/groins, and piers/ramps/docks. Semi-submerged marshes, referred to here as "low marshes," ocurring where it is possible to discern marsh-like features waterward of the shoreline are also included. Off shore and riverine islands and rocks may be included depending on the quality of their depiction on the t-sheet. It does not include any non shoreline-centric elements that may have been depicted on the t-sheets such as buildings, roads, bridges, etc., nor does it include other off-shore features like sandbars, mud flats, tidal flats, etc. Features are line locations that represent the approximate location of shoreline features and wetland boundaries. Shoreline, as depicted on the T-sheets that pre-date 1927, reference an approximation of Mean High Water (MHW). Although MHW is technically determined by averaging the height of the high water line, (HWL) the landward extent of the last high tide over a 19 year lunar cycle, USC&GS topographers appoximated MHW by familarizing themselves with the tidal conditions in a given area and noting the assorted physical characteristics of the beach. (For a more complete description of this and other shoreline indicators, the reader is directed to the following article: "Historical Shoreline Change: Error Analysis and Mapping Accuracy," Crowell, M., Leatherman, S., and Buckley, M. Journal of Coastal Research, Vol 7, No. 3, 1991, pp 839-852.) Attribute information is comprised of codes to identify individual features, encode shoreline feature type information, and cartographically represent (symbolize) shoreline features on a map. These codes were derived in part from the National Oceanic & Atmospheric Administration (NOAA) Coastal Services Center (CSC) Historic Digital Shoreline Capture project and modified by the State of Connecticut Department of Environmental Protection to address the inclusion of wetland areas. This data was compiled at 1:10,000 scale. This data is not updated. Purpose: 1880s NOS T-Sheet Shoreline Features is 1:10,000-scale data. It depicts the location of historic shoreline features and wetland boundaries for all of coastal Connecticut with the exception of the area of New Haven Harbor from the West River in West Haven to the New Haven/East Haven town boundary. The features also extend slightly beyond the Connecticut state lines into Rye, New York and Westerly, Rhode Island. Use this layer to display historic shoreline and wetlands. Since this data may be considered a crucial element in land use planning, determination of boundary extents, performing change studies for erosion and accretion examinations and other types of decision making this layer may also be used for analytic purposes. Use this layer with other 1:10,000-scale map data such as any other NOS T-sheet Shoreline or Wetland layers. Not intended for maps printed at map scales greater or more detailed than 1:10,000 scale (1 inch = 833.33 feet.) 1880s NOS T-Sheet Wetland Polygon Features is a 1:10,000-scale, polygon feature-based layer that includes information depicting historic wetlands for areas of coastal Connecticut during the 1880s. The layer depicts information found on topographic survey sheets (T-sheets) from the US Coast and Geodetic Survey (USC&GS), a predecessor to