Interstate 35 splits into Interstates 35E and 35W to serve Dallas (east) and Fort Worth (west). The two routes diverge north of Hillsboro, through rural reaches of Hall County and reconvene on the west side of Denton.
Interstate 35W angles northwest to Grandview and Alvarado through rural areas of Johnson County before crossing the Tarrant County line at Burleson. A business route serves Alvarado, near the junction with U.S. 67. It is signed as Business Loop I-35 versus 35W. IH 35W (South Freeway) passes west of Fort Worth Spinks Airport (FWS) through an area of retail in south Fort Worth. The freeway advances northward by a large industrial park to Interstate 20 near the town of Edgecliff Village.
IH 35W bisects central Fort Worth to Downtown, where it meets Interstate 30, U.S. 287 (Martin Luther King, Jr. Freeway) and Texas 121 (Airport Freeway). U.S. 287 combines with IH 35W north from there across the Trinity River West Fork through another industrial park area ahead of Interstate 820.
A wye interchange separates U.S. 287 from IH 35W beyond residential subdivisions along Basswood Boulevard. This split represents the northbound beginning of U.S. 81, which IH 35 and IH 35W replaced southward to Laredo. Passing by Fort Worth Alliance Airport (AFW), Interstate 35W (North Freeway) crosses the Denton County line en route to Northlake and Texas Motor Speedway. The remainder of the route west of Argyle and through south Denton is mostly rural to the merge with IH 35E.
The American Association of State Highway and Transportation Officials (AASHTO) mandated that all suffixed Interstate highways be renumbered to eliminate confusion. Similar to the Interstate 35E and 35W branch split in Minnesota, the reason IH 35E and 35W remain in Texas is that neither Dallas nor Fort Worth wanted to relinquish the routing of Interstate 35.
The South Freeway was one of the first Fort Worth area freeways built. The initial stretch was constructed starting on April 7, 1947 between Seminary Drive (Exit 46A) and Morningside Drive (north of Exit 48A). It was opened on September 14, 1949 as a new alignment for U.S. 81. Subsequent sections of the South Freeway opened north from Morningside Drive and Rosedale Street on November 30, 1951, from Rosedale Street to IH 30 in March 1955 and between Seminary Drive and Altamesa Boulevard that same year.1
Construction on the North Freeway commenced north of IH 30 in 1958, but was delayed one year due to litigation. The stretch between IH 30 and Yucca Avenue north of the Trinity River West Fork opened in May 1962. Extensions followed northward from Yucca Avenue to 28th Street in 1963, from 28th Street to IH 820 in 1966 and from IH 820 to Texas 114 in Denton County in August 1967. The route was completed north to Denton on July 3, 1969, with the interchange at IH 35E finished on April 15, 1970.1