The Katy Trail is actually a Rail-to-Trail project, the largest ever developed at 240 miles long, crossing the state of Missouri. The trail itself has a mix of surfaces, but most the trail is crushed limestone. There are several towns within 5 miles of each on the trail making it easy to resupply. The Katy Trail is a multi-use trail for hikers, bicyclists, and even equestrians. The section of trail between Cooper County and St. Charles County has been designated as an official segment of the Lewis and Clark National Historic Trail. The Katy Trail is also a part of the American Discovery Trail.