Most of the flow into the lake comes from the Kissimmee River. The river ends at the lake and extends north for a hundred miles, through a chain of lakes connected by canals, to Orlando. The Kissimmee was shortened by nearly 50 miles when channelized by the Army Corps of Engineers in the 1960s and 1970s. Despite efforts to reverse this (for environmental reasons), much of the river still flows though straightened channels.