U.S. Route 24 in Kansas

US-24 enters the state from Colorado concurrent with I-70 southwest of Kanorado. For its first 46.061 miles (74.128 km), the route runs concurrently with the Interstate, passing Goodland and Brewster. This is despite the fact that former alignment remains intact, albeit largely as a local road. The exception to this rule is a business route through downtown Goodland.

South-southwest of Levant, US-24 splits from the Interstate and begins heading northeastward before eastward and into Colby. The route passes through the northern side of town, intersecting K-25 before continuing east. Toward the Thomas–Sheridan county line, US-24 intersects US-83 in an extremely rural setting southeast of the town of Gem. The route continues through Sheridan, Graham, and Rooks counties, passing through the towns of Hoxie, Hill City, and Stockton and intersecting K-23, US-283, K-18, and US-183. US-24 also passes by several other smaller communities, such as Menlo and Morland, connecting to those towns via secondary state highways. Additionally, the route passes around the northern edge of the Webster Reservoir in western Rooks County.

In Osborne, the highway joins US-281 and begins heading northward. South of Portis, US-24 leaves US-281 and returns to an eastward trajectory, picking up a concurrency with K-9 in the process. The route passes through Downs and Cawker City, around Waconda Lake, and into Beloit. In Beloit, it junctions K-14, before K-9 splits toward the east as US-24 begins a southeastward run to Glasco, where it returns to an eastward trajectory. East of that town, the route crosses US-81 in another rural setting. US-24 continues through Clay County and Clay Center and into Riley County.

Shortly after Leonardville, US-24 takes a sharp rightward turn before intersecting US-77 on the north side of Riley, returning to an eastward direction and running concurrently. The routes split shortly thereafter as US-24 begins heading southeast toward Manhattan. The route passes around the city to the northeast and east sides, before splitting away from town at K-177 and heading across the Big Blue River and into Pottawatomie County.

US-24 eastbound east of Perry

Concurrency of US-24 and US-59 near Williamstown

US-24 runs across the southern edge of the county parallel to the Kansas River, passing through Wamego, Belvue, and St. Marys. Entering Shawnee, the county begins heading southeastward toward Topeka via Rossville and Silver Lake. US-24 passes across the northern end of Topeka as a hybrid limited-access road, with four interchanges in and around the city, including ones with US-75 and K-4, with a short concurrency between interchanges with the last route. US-24 continues eastward, paralleling the Kansas River through Jefferson County, passing through Grantville and Perry, then picking up a concurrency with US-59 north of Williamstown. The routes then turn south toward Lawrence, with US-24 splitting to the east and gaining a concurrency with US-40 on the north side of the city as US-59 and US-40 west head south toward downtown. US-24/US-40 heads northeast toward Tonganoxie, where it turns east once again. On the Kansas City–Bonner Springs city line, the two routes intersect US-73 and K-7 at a cloverleaf interchange, where US-24/US-40 joins US-73/K-7 southward toward I-70 and Bonner Springs. At I-70, US-24 and US-40 join the Interstate Highway eastward, while US-73 ends and K-7 continues southward into the core of Bonner Springs. US-24 continues with I-70 into Kansas City and across the Kansas River into Kansas City, Missouri.

When the United States Numbered Highway System was first instituted in 1926, much of what is now US-24 was designated as U.S. Highway 40N (US-40N). US-40N ran along present-day US-24 between Limon, Colorado, and Manhattan. At Manhattan, it and US-40S recombined into US-40, which used the present alignment of US-24 eastward toward Topeka. Between Topeka and Lawrence, K-10 occupied the current alignment of US-24 as US-40 used its still standing alignment on the south side of the Kansas River. At Lawrence, US-40 returned to using US-24's alignment onto Kansas City and Missouri. In 1935, US-40N was decommissioned and US-24 was extended westward from its previous terminus at Independence across the state into Colorado and eventually on to Grand Junction, Colorado (later reduced to Minturn, Colorado).[4]