Geography

The 2010 Census Block Relationship files are provided as a tool to help data users compare the universe of Census 2000 blocks to the universe of 2010 Census blocks. From these files, data users may determine how 2000 blocks now relate to 2010 Census blocks and vice versa. Please use the links below to find out more information about the 2010 Census Block Relationship files and to download them.

• Overview of the 2010 Census Block Relationship Files
• Understanding the 2010 Census Block Relationship Files [PDF]
• Download the 2010 Census Block Relationship Files
• 2010 Census Block Relationship File Format and Record Layout
• Census 2000 Block Relationship Files

The Congressional District Relationship files provide simple relationships between the specified Congressional District and other Census 2000 tabulation geography:  American Indian Areas, counties, census tracts, places, school districts, urban/rural population and land area, and ZIP Code Tabulation Areas. The links below provide more information about the relationship files, including format and layouts, as well as a link to the files.

• About Congressional Districts
• Download State-based Relationship Files for the 108th - 110th Congressional Districts
• Download Nation-based Relationship Files for the 109th and 110th Congresses

The 2010 Census Tract Relationship files are provided as a tool to help data users compare the universe of Census 2000 tracts to the universe of 2010 Census tracts. From these files, data users may determine how Census 2000 tracts relate to 2010 Census tracts and vice versa. The links below provide more information about the relationship files, including format and layouts, as well as a link to the files.

• Overview of the 2010 Census Tract Relationship Files
• Understanding the 2010 Census Tract Relationship Files [PDF]
• Download the 2010 Census Tract Relationship Files
• 2010 Census Tract Relationship File Format and Record Layout
• Census 2000 Tract Relationship Files

The 2010 census tract to military area relationship file is provided as a tool for data users interested in understanding which census tracts contain a military base or outlying area. Census tracts do not necessarily nest within military areas, so the list includes all census tracts that contain any amount of military area. The total area of the intersection between the census tract and military area is provided, as well as the percentage of the census tract covered. The list does not contain all 2010 census tracts. It only contains the census tracts that intersect with a military area. Military areas are updated occasionally; however, we do not have plans to create an updated relationship file at this time. The list is accurate as of October 2012.

• Download the 2010 Census Tract to Military Area Relationship File
• 2010 Census Tract to Military Area Relationship File Format and Record Layout

The 2010 urban area relationship files provide simple relationships between the 2010 urban areas and other 2010 Census tabulation geography: counties, county subdivisions (in states with governmental minor civil divisions only), places (incorporated places and census designated places), metropolitan and micropolitan statistical areas, New England city and town metropolitan and micropolitan statistical areas (NECTAs), and ZIP Code tabulation areas (ZCTAs). A 2010 urban area relationship file also describes the relationship between 2010 and Census 2000 urban areas. From these files, data users may determine which urban areas exist within the other geographies and vice versa.

• Overview of the Urban Area Relationship Files
• Download the 2010 Urban Area Relationship Files
• 2010 Urban Area Relationship File Record Layouts

For more information on urban areas, please see our 2010 Census Urban Areas page.

For more information on specific Geographies, please see the 2010 Census Geographic Terms and Concepts.

The 2010 ZIP Code Tabulation Area (ZCTA) Relationship files provide simple relationships between the 2010 ZCTAs and other 2010 Census tabulation geography. From these files, data users may determine which ZCTAs exist within the other geographies and vice versa. Please use the links below to find out more about the 2010 ZCTA Relationship files.

• Overview of the 2010 ZIP Code Tabulation Area (ZCTA) Relationship Files
• Download the 2010 ZIP Code Tabulation Area (ZCTA) Relationship Files
• 2010 ZIP Code Tabulation Area (ZCTA) Relationship File Record Layout