Douglas County, Kansas, maintains an extensive network of county highways to serve the rural areas and state parks of the county. It is one of a handful of Kansas counties to do so.
The major county highways are set up on a grid. EastâÂÂwest-oriented roads have a three-digit number beginning with the numeral "4" and ending in an even digit. The further north the road, the lower the number; the further south, the higher the number. NorthâÂÂsouth-oriented roads have a four-digit number beginning with "10" and ending in an odd digit. The further west the road, the lower the number; the further east, the higher the number.
There are also minor county roads with one or two digits that travel a short distance or serve a state park.
None of the county highways enters Lawrence, the county seat.
The maximum speed limit on all county highways in Douglas County is .