Extracting the boundaries of each county is useful for many applications of the TIGER dataset. The following Java-based tools allow one to download the TIGER Lines corresponding to any state of your choice. This boundary data is much smaller than the entire dataset for the state, and hence the tool avoids downloading the entire dataset. Merging the boundaries of adjacent counties is a slight problem, as TIGER Lines are not necessarily consistent across counties. We give a simple (imperfect) solution with the Merge program below.
For our user's convenience, we have also provided (1) a simple drawing tool to visualize the boundaries so extracted, and (2) downloadable pre-processed boundary data for each state.
BUG FIX: The following bug was recently fixed (12/1/2001). When the integer part of longitude turns from two to three decimal digits (in western USA), the minus sign in longitude disappears from our data below. For example, bounding coordinates for NY are (-79762418, -71778137, 40477408, 45010840). But for CA, it is (114132652, 124470153, 32528832, 42009518). The longitude in the bounding box for CA are missing their negative signs: Thanks to Alex Gleyzer for this bug report.
State | Segments in County Boundaries | Monotone Chains in County Boundaries | |
---|---|---|---|
AK | Download(3401 segments) | Download(804 chains) | |
AL | Download(15372 segments) | Download(2240 chains) | |
AR | Download(18204 segments) | Download(2888 chains) | |
AZ | Download(7736 segments) | Download(1047 chains) | |
CA | Download(20513 segments) | Download(3680 chains) | |
CO | Download(15107 segments) | Download(3075 chains) | |
CT | Download(2328 segments) | Download(247 chains) | |
DC | Download(393 segments) | Download(11 chains) | |
DE | Download(1020 segments) | Download(103 chains) | |
FL | Download(14097 segments) | Download(2545 chains) | |
GA | Download(27317 segments) | Download(4430 chains) | |
GU | Download(87 segments) | Download(5 chains) | |
HI | Download(639 segments) | Download(145 chains) | |
IA | Download(15892 segments) | Download(2421 chains) | |
ID | Download(12824 segments) | Download(2063 chains) | |
IL | Download(20679 segments) | Download(3014 chains) | |
IN | Download(14704 segments) | Download(2074 chains) | |
KS | Download(20309 segments) | Download(3720 chains) | |
KY | Download(20213 segments) | Download(3794 chains) | |
LA | Download(15406 segments) | Download(2766 chains) | |
MA | Download(3969 segments) | Download(433 chains) | |
MD | Download(6228 segments) | Download(793 chains) | |
ME | Download(4131 segments) | Download(508 chains) | |
MI | Download(15585 segments) | Download(2096 chains) | |
MN | Download(19099 segments) | Download(3069 chains) | |
MO | Download(23388 segments) | Download(3021 chains) | |
MS | Download(16364 segments) | Download(2607 chains) | |
MT | Download(17465 segments) | Download(3319 chains) | |
NC | Download(19310 segments) | Download(3258 chains) | |
ND | Download(13855 segments) | Download(2908 chains) | |
NE | Download(17743 segments) | Download(3635 chains) | |
NH | Download(2872 segments) | Download(292 chains) | |
NJ | Download(5109 segments) | Download(712 chains) | |
NM | Download(10554 segments) | Download(1647 chains) | |
NV | Download(6600 segments) | Download(775 chains) | |
NY | Download(13854 segments) | Download(1746 chains) | |
OH | Download(17059 segments) | Download(1687 chains) | |
OK | Download(19072 segments) | Download(3139 chains) | |
OR | Download(12200 segments) | Download(1896 chains) | |
PA | Download(16257 segments) | Download(2075 chains) | |
PR | Download(10355 segments) | Download(2224 chains) | |
RI | Download(962 segments) | Download(83 chains) | |
SC | Download(10837 segments) | Download(1731 chains) | |
SD | Download(14663 segments) | Download(2999 chains) | |
TN | Download(19837 segments) | Download(3923 chains) | |
TX | Download(48403 segments) | Download(6831 chains) | |
UT | Download(8644 segments) | Download(1575 chains) | |
VA | Download(22800 segments) | Download(4539 chains) | |
VI | Download(63 segments) | Download(15 chains) | |
VT | Download(2592 segments) | Download(341 chains) | |
WA | Download(10086 segments) | Download(1725 chains) | |
WI | Download(14360 segments) | Download(2081 chains) | |
WV | Download(12730 segments) | Download(1845 chains) | |
WY | Download(7912 segments) | Download(1036 chains) |