The state highways in Harris County, Texas consists of approximately of routes in the Texas state highway system that are located within Harris County. These highways are maintained by the Texas Department of Transportation. These highways are made up of Interstate Highways, U.S. Highways, State Highways, State Loop and Spur Highways, Farm to Market Roads, Park Highways, and Alternate and Business Routes. In addition to these highways, three independent Toll Roads and a section of Interstate 10 that is toll managed are also located in Harris County. These roads are maintained by the Harris County Toll Road Authority, and add approximately of highways to the overall Harris County highway system. There are four interstates located within Harris County. They consist of three major interstates, known as the Katy Freeway and the East Freeway, Interstate 45, known as the Gulf Freeway and the North Freeway, and Interstate 69 and one Auxiliary Interstate. There are also three U.S. Routes located in Harris County. These highways consist of U.S. Route 59, U.S. Route 90, and U.S. Route 290. There are nine state highways, eight spur and loop highways, one park highway, six toll roads, twenty-two farm to market roads, four bannered U.S. routes, two bannered state routes, and one bannered farm to market road.
Highways
Interstate Highways and U.S. Highways
There are four interstate highways located in Harris County. These interstates are I-10, which runs west–east, I-45, which runs south–north, I-69, which also runs south-north, and I-610, which forms a small loop around Downtown Houston. I-10 and I-45 run concurrently with each other for a short distance in Downtown Houston. I-10 was created in 1959, with the establishment the Interstate Highway System; I-45 was created in 1971; the first segment of I-69 was created on July 26, 2012, the second segment was created on February 28, 2013, the third and final segment was created on March 25, 2015, when it is fully complete the mainline of I-69 will run from the U.S.–Mexico border in Brownsville to the U.S.–Canada border in Port Huron, MI; I-610 was created in 1959, with the establishment of the Interstate Highway System. In addition to the four interstate highways, there are also three U.S. Routes. These highways are US 59, which forms the Southwest and Eastex Freeways, and runs southwest-northeast, US 90, which runs concurrently with I-10 from the west county border to I-610, where it becomes the Cosby Freeway, running in a west–east direction, and US 290, which forms the Northwest Freeway, running southeast-northwest.
State Highways, Loops, Spurs, and Park Roads
There are currently nine state highways located in Harris County. The longest of these is Texas State Highway 6, which stretches approximately from the Fort Bend County line to the Waller County line. The shortest of these is Texas State Highway 35, which stretches approximately from the Fort Bend County line to Interstate 45 in south Houston. NASA Road 1 is also located in Harris County, and is one of just two state highways in Texas that is not numbered. The other highway is State Highway OSR. There are currently only one loop highway in Harris County, Texas State Highway Loop 494, which has its south end at I-69 just south of the Harris-Montgomery county line, and Beltway 8, the state's only highway designated as a beltway, forms a large loop around most of Houston. There are six spur routes located in Harris County. The longest is Texas State Highway Spur 261, at long. The shortest spur is Texas State Highway Spur 330, at. There is currently one park road located in Harris County, Texas Park Road 1836. Park Road 1836 serves the San Jacinto Battleground State Historic Site and Battleship Texas. The highway is numbered 1836 to commemorate Texas's year of independence. Park Road 1836 is long.
There are currently twenty-two farm to market roads located in Harris County. Due to the heavy urbanization of Harris County, many of these FM's have been redesignated to Urban Roads under the TxDOT standards, but are still officially signed as Farm to Market Roads. The length of these Farm to Market Roads varies from approximately long to just .
Toll Roads
There are seven toll roads located in Harris County. Three of these toll roads are independent toll roads. These consist of the Hardy Toll Road, the Westpark Tollway, and the Fort Bend Toll Parkway. The other four toll roads are state-maintained highways that have been converted to toll highways. These are the Sam Houston Tollway, the Tomball Tollway, the Katy Managed Lanes, which is a section of Interstate 10 located between Katy and downtown Houston, and the Grand Parkway which is under construction. All toll roads are maintained by the Harris County Toll Road Authority, and are marked with a purple and yellow version of the county highway shield.
Interstate Highways
U.S. Highways
State Highways
State Highway Loops and Spurs
State Park Roads
Toll Roads
All Harris County toll roads are maintained by the Harris County Toll Road Authority.
