Reference marker maps
These commonly requested maps show reference markers for each county in Texas and are used for a wide variety of purposes both inside and outside TxDOT.
A reference marker is a small green placard displaying a three-digit number that’s placed at intervals along all state-designated routes in Texas. Reference markers are used by TxDOT and the Texas Department of Public Safety as general reference points for identifying locations of vehicle incidents or roadway work.
This map series is updated annually, typically mid-summer, following the publication of end-of-year data from the previous calendar year.
Each zip file contains multiple county-level maps within each TxDOT district.