Interstate 35W (Texas)

Interstate 35W (I-35W), an Interstate Highway, is the western half of I-35 where it splits to serve the Dallas–Fort Worth metropolitan area. I-35 splits into two branch routes, I-35W and I-35E, at Hillsboro. I-35W runs north for 85.2 miles (137.1 km), carrying its own separate sequence of exit numbers. It runs through Fort Worth before rejoining with I-35E to reform I-35 in Denton. It is the more direct route for long-distance expressway traffic, as is noted on signs on I-35 leading into the I-35W/I-35E splits. During the 1970s, billboards existed on I-35 encouraging travelers to take the faster and shorter I-35W route.

During the early years of the Interstate Highway System, branching Interstates with directional suffixes, such as N, S, E, and W, were common nationwide. On every other Interstate nationwide, these directional suffixes have been phased out by redesignating the suffixed route numbers with a loop or spur route number designation (such as I-270 in Maryland, which was once I-70S) or, in some cases, were assigned a different route number (such as I-76, which was once I-80S). In the case of I-35 in the Dallas–Fort Worth area, since neither branch is clearly the main route and both branches return to a unified Interstate beyond the cities of Dallas and Fort Worth, officials at the American Association of State Highway and Transportation Officials (AASHTO) have allowed the suffixes of E and W in Texas to remain in the present day. I-35 also splits into I-35E and I-35W in Minneapolis–Saint Paul, Minnesota, for similar reasons as the I-35 split in the Dallas–Fort Worth area.