Harris and Dallas counties have the dubious honor of claiming the most spots in the state's latest list of the 100 most congested roadways in Texas.

The Texas A&M Transportation Institute has compiled the list, which was released Friday, for the Texas Department of Transportation annually since 2010. TTI officials said this report is the most accurate yet, incorporating more complete data of traffic and vehicle speeds across the state.

Texas' most populated county, Harris County, has 38 road segments on the list, followed by Dallas County with 20, Tarrant County with 13, Travis County with 12 and Bexar County with seven.

The table below shows the state's 100 most congested road segments based on annual average hours of delay per mile. "Peak period average speed" shows the average speed recorded during the rush hour periods of 6 a.m. to 9 a.m. and 4 p.m. to 7 p.m. "Average uncongested speed" presents the average speed recorded during light traffic conditions, usually overnight.