Katy Trail
The Katy Trail State Park is a Missouri state park and a 225-mile recreation rail trail that runs from St. Charles near the confluence of the Mississippi and Missouri Rivers to Clinton, which is about 75 miles southeast of Kansas City. The trail is commonly known as the Katy Trail as it follows the right of way of the former Missouri-Kansas-Texas Railroad and is the longest Rails-to-Trails trail in the United States.

The Missouri-Kansas-Texas Railroad ceased operation from Sedalia to Machens in 1986 and the Missouri Department of Natural Resources began to acquire the right of way. The National Trails System Act of 1968 made conversion of the corridor from a railroad to a trail possible.

One hundred sixty five miles of the Katy Trail State Park has been designated an official segment of the Lewis and Clark National Historic Trail and the trail from St. Charles to Boonville is part of the American Discovery Trail. Most of the trail follows the northern bank of the Missouri River. The trail is open for use by hikers, joggers, and cyclists year-round. The St. Charles to Augusta leg in St. Charles County is popular with residents of metropolitan St. Louis.

County Parks
The St. Charles County Parks Department builds and maintains several miles of trails for visitors to its many parks. Three types of trails are featured within the park:
  • Hiking / Biking Trails: Which feature a natural terrain and access more remote places within the park
  • Multi-Use Trails: Which feature a natural terrain and are the county's first public parkland open to equestrian day-use, as well as hikers and cyclists
  • Paved Trails: Which are covered with asphalt and located near parking lots, picnic shelters, and other park structures
Trails Within St. Charles County Parks
  • Bangert Island: 4 miles of natural trail
  • Broemmelsiek Park: 7 miles of natural trail and 1/2 mile of paved surface
  • Indian Camp Creek Park: 10 miles of natural trail and 1/2 mile of paved surface
  • Klondike Park: 3 miles of natural trail and 3/4 miles of paved surface
  • Matson Hill Park: 6 plus miles of natural trail
  • Quail Ridge Park: 4 miles of natural trail and 3 miles of paved surface
  • Towne Park: 2 plus miles of natural trail and 1/4 mile of paved surface
  • Youth Activity Park: 1/2 mile of paved surface
Bike Trails
There are several bicycle trails throughout St. Charles County.
Trail Name Trail Length in Miles
Barat Haven Trail
Boschert Trail
Cottleville Trail
Dardenne Greenway at Bluebird Meadow
Katy Trail to Heritage Museum
Missouri Research Park Trail