Interstate 135
| Map of Kansas with I-135 highlighted in red | ||||
| Route information | ||||
| Auxiliary route of I-35 | ||||
| Maintained by KDOT | ||||
| Length | 95.738 mi (154.075 km) | |||
| Existed | September 13, 1976–present | |||
| NHS | Entire route | |||
| Major junctions | ||||
| South end | I-35 / Kansas Turnpike in Wichita | |||
| North end | I-70 / US-40 / US-81 in Salina | |||
| Location | ||||
| Country | United States | |||
| State | Kansas | |||
| Counties | Sedgwick, Harvey, McPherson, Saline | |||
| Highway system | ||||
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Interstate 135 (I-135) is an approximately 95.7-mile-long (154.0 km) auxiliary Interstate Highway in central and south-central Kansas, United States. I-135, which is signed as north–south, runs between I-35 and the Kansas Turnpike in Wichita north to I-70, U.S. Highway 40 (US-40), and US-81 in Salina. Except for the first 0.46 miles (0.74 km), I-135 overlaps US-81 its entire length. The route also runs through the cities of McPherson, Newton, and Park City.
The highway was designated as Interstate 35W (I-35W) until September 1976, when it was renumbered as I-135 to conform to new AASHTO policies that eliminated most suffixed Interstate Highways. It is currently the longest three-digit spur with an odd first digit in the Interstate System.