K-31 is a 134-mile (216 km) long state highway in the U.S. state of Kansas. K-31 is signed as east–west from US-69 in Fulton to US-59 west of Kincaid and is signed as north–south from US-59 west of Kincaid to K-99 west of Harveyville. K-31 runs diagonally southeast–northwest, connecting small towns in east-central Kansas.

Interstate 35 (I-35) is an Interstate Highway in the US that runs from the Mexican border near Laredo, Texas, to Duluth, Minnesota. In Kansas, the highway goes from the Oklahoma border to Kansas City at the Missouri border, with a length of 235 miles (378 km). Along the way, I-35 passes through Wichita, the state's largest city, linking it to Emporia, Ottawa, and Kansas City and its Johnson County suburbs. The section of the route from the Oklahoma border to I-335 is part of the Kansas Turnpike.