Paul, Minn., in the capacity of its grain elevators. The Kansas City Livestock Exchange is one of the largest in the United States. A vast system of limestone mines lies beneath the metropolitan area. Many of these mines have been converted into warehouses. About 10 major railroad freight lines serve Kansas City, one of the busiest U.S. rail centers.
Passenger trains link the metropolitan area to other cities.
Kansas City is also a center for trucking transportation. Kansas City International Airport is the city's main air terminal. Three barge lines operate on the Missouri River. Federal, state, and local governments employ about 15 percent of the workers in the Kansas City area. The more than 1,700 manufacturing firms in metropolitan Kansas City employ about 20 percent of the area's workers.