The longest Rails-to-Trails project in the country, and Missouri's "skinniest state park" turns 25 years old this year. After weathering floods, storms and even a tornado, the 240-mile long Katy Trail attracts hundreds of thousands of visitors annually.

The trail is 240-miles of hard, packed gravel, bisecting the state with a chain of small towns and rest stops from St. Charles to Clinton, MO dotting its path. It follows the route of the old Katy Railroad, which stopped running in the 1980s; a casualty to the rise of 18-wheeler trucks for hauling freight.

Durrie Bouscaren | St. Louis Public Radio

Left with miles of unused train tracks, Congress passed the National Trails Systems Act, which included a provision to convert old train tracks to trails for use by the public. In this way, the trails could be rebuilt quickly along the routes, in a process known as "railbanking." This was met with opposition from property owners who had given up some of their land when the rails were built and believed the land should return to them.

The first few miles of the Katy Trail opened in 1990, but devastating floods along the Missouri river wiped out about 150 miles the next year, said trail coordinator Dawn Fredricksen. Large swaths of the trail had to be rebuilt, delaying the trail's official opening.

Durrie Bouscaren | St. Louis Public Radio

Today, the state of Missouri estimates that 400,000 people visit the Katy Trail each year for bicycling, walking and watching native wildlife such as the electric blue indigo bunting. Sometimes, cyclists ride the whole thing from start to finish, camping or staying in small towns along the way.

One cyclist, John Femmer of Maryland Heights, said he lived next to the railroad as a child.

Durrie Bouscaren | St. Louis Public Radio

"At 7:20 the train would go by every evening. The clickety-clack of the train crossing the track there put me right to sleep every day," Femmer said. Today, he rides the trail on his bike regularly, to help him recuperate after knee surgery.

"There's this produce store, and there’s a lady in there. When I stop there, that’s my 14-mile mark, and she has pies. I call her the pie lady," Femmer said.

The pie lady’s name is Fran Thies. She’s the manager at Thies Farm in St. Charles. In the summer, she says, half of her weekend customers are trail riders. Hers is one of many other restaurants, campsites and bed and breakfasts that have built their business around the trail.

"They come like it’s a mirage: do you have water, do you have air for the tires? And, of course, you get a slice of pie too while you wait," she laughs. The store also offers home grown fruit and vegetables. Thies has been known to microwave a potato or two for cyclists who say they're craving carbs.

Durrie Bouscaren | St. Louis Public Radio

Durrie Bouscaren | St. Louis Public Radio

Thies has fond memories of visitors from the trail, including an 85-year-old woman who said it was her birthday.

"Her gift was to walk the trail. So, she had an RV following her, and she was walking the trail for six days," Thies said.

Next month, hundreds of bicyclists will embark on a week-long ride along the entire length of the trail from Clinton to St. Charles. This time, they’ll also celebrate the trail’s 25th anniversary.

Durrie Bouscaren | St. Louis Public Radio

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