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 and east to IH 69 north of Humble.
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.
IH 610 was approved by the Texas State Highway Commission in 1962 and by AASHO on June 30, 1970. Plans in the 1950s assigned Loop 137 along the southern, western, and northern portions of the beltway. The eastern section and the bridge across the Houston Ship Channel were not included in the Loop 137 plans, but they were added to the IH 610 approval in 1962. The entire loop route was open to traffic by 1975.1