I-435, a loop route of I-35, is long and intersects with nearly every other interstate highway in the Kansas City area. An additional near Kansas City International Airport is signed along with I-29 and U.S. Route 71, making I-435 the second-longest complete beltway numbered as a single Interstate Highway in the U.S., and seventh longest in the world after Cincinnati, Ohio's I-275 at, Houston, Texas's Beltway 8 at, Berlin's Bundesautobahn 10 at, and London's M25 motorway at as well as Beijing’s 7th and 8th ring roads. The majority——of I-435 is within the state of Missouri, and most of that roadway lies within the city limits of Kansas City. The first/last exit is at I-435's parent route, I-35, in Lenexa, Kansas. Going clockwise around Kansas City, the next interchange is exit 1A for Lackman Road. The milepost numbers do not start over when I-435 crosses the state line, but where it shares the same roadway as I-29, the latter's milepost numbering takes precedence.
History
I-435 in Kansas City was built piece by piece starting in the mid-1960s and not finished until 1987. In 1965, the first segment of I-435 was built and opened between I-35 and US-69 near Overland Park, Kansas. A second segment was opened the same year between I-70 and US-50 in eastern Kansas City, Missouri, but the two were not connected. By 1968, the eastern segment of I-435 was extended south to Gregory Boulevard and north past 23rd Street/Route 78. By 1969, I-435 was fully built between these two segments, through southern and eastern Kansas City. By 1971, the freeway was extended from 23rd Street/Route 78 to US-24. In 1973, I-435 was extended north from the former terminus of US-24 across the Missouri River to I-35 in Claycomo. It now extended halfway around the city. In 1983, a small segment was opened on the outskirts of Kansas City north between US-169 and Route 291 near Kansas City International Airport. By 1985, this small segment was connected with the rest of the freeway. A segment was built heading almost due north from I-35 in Claycomo to Route 291/Cookingham Drive at North Reinking Road, curving due west from there to US-169. In this year, the southwest end was also extended to K-10. In 1987, the freeway was opened all the way around the city. The northwest end was signed on I-29 for northwest, then exited, near Platte City and bore south on the west side of KCI. It crossed several small highways before crossing the Missouri River into Wyandotte County, Kansas. It continued generally south or southwest, crossed several state highways and I-70, then the Kaw River, before connecting with the former southwest end at K-10.
