The Katy Trail is a 239 mile trail stretching across most of Missouri. It is America's longest "rails-to-trail" project, formerly the MKT rail line. Over half of it follows the Lewis and Clark's path up the Missouri River. If you are planning to do the entire trail, you will want to drop off a vehicle at the end destination, making this a one-way adventure. The trail follows large river bluffs that then lead through quiet farmland. Many cross-country cyclists include the Katy Trail in their tours. The recommended tire width for the trail is 25mm or wider. Running is very popular on the for long distance runs, because of its nice and flat surroundings. Also, the crushed limestone trail surface is easy on your legs. There are long distances without access to water, so runners and hikers should carry water and plan ahead. There are expeditions along parts of the trail where the towns offer water, groceries, or vending machines that are not too far apart.