Known as the Loop or the 610 Loop, Interstate 610 constitutes the inner beltway for the city of Houston. The middle beltway is the Sam Houston Parkway / Tollway and Beltway 8. Further out from the city, Grand Parkway (SH 99) is the outer beltway around the Houston metropolitan area. The toll road forms a semicircle north from IH 69/U.S. 59 near Sugar Land to Tomball, east to IH 69 north of Humble, and south to SH 146 at Baytown.
Interstate 610 provides connectivity to metropolitan area freeways radiating out of Houston including U.S. 90 (Crosby Freeway), U.S. 290 (Northwest Freeway) and SH 288 (South Freeway) among the Interstate connections with IH 10, IH 45 and IH 69/U.S. 59. The 610 Loop is heavily traveled freeway varying between six to eight lanes with multi level systems interchanges at intersecting freeways.
Plans in the 1950s assigned Loop 137 along the southern, western, and northern portions of the beltway encircling Houston. The eastern section and the bridge across the Houston Ship Channel were not included in the Loop 137 plans.1 Interstate 610 was part of the Texas urban Interstate numerology approved by the American Association of State Highway Officials (AASHO) on November 10, 1958. IH 610 was outlined as a nearly complete beltway replacing Loop 137 with the exception of the southeastern quadrant, between IH 45 and IH 10.
IH 610 was approved by the Texas State Highway Commission on October 16, 1959. The missing link between IH 10 in east Houston to IH 45 in southeast Houston was approved as IH 610 by the commission on September 17, 1962. That section was formally added to the Interstate Highway system by AASHO on June 30, 1970. The entire loop along Interstate 610 was open to traffic by 1975.1