Tiger Data Information
Describing the Converted Data
Tiger data is very complex, and it consists of data represented by points, lines,
and polygons. An ESRI Shapefile can only represent one type of data, and all of the
data in the file must be of the same general type (streets, water, etc). To accomplish
the conversion, we selected subsets of the Tiger data and converted each subset into a
separate Shapefile.
To help keep the data organized, we prefixed the name of each Shapefile with the
string TgrSSCCC, where SS is the ISO state code and CCC is the ISO county code. So,
for instance, the shapefiles for Polk County, Iowa all start with Tgr19153, where 19
is the ISO code for Iowa, and 153 is the ISO county code for Polk County in Iowa.
The Tiger data that we provide, and the Shapefiles to which the data was converted are:
Category A (major roads) |
TgrsscccLKA |
Category B (minor roads) |
TgrsscccLKB |
Category C (rail, paths, etc) |
TgrsscccLKC |
Category H (streams and rivers) |
TgrsscccLKH |
Category H (bodies of water) |
TgrsscccWAT |
Political subdivisions |
TgrsscccCCDCU |
City boundaries |
TgrsscccCTYCU |
Urban Areas |
TgrsscccURB |
You can learn more about the data contained within each Shapefile by reviewing the
USGS Tiger97 Technical Documentation
The source Tiger data and the tool to convert the Tiger data to Shapefile format was purchased from
Blue Marble Geographics.
They have just recently announced the availability of Tiger99 data, and we will be updating our
shapefile conversions to use this newly acquired data in the near future.
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