Ken from St. Charles on 4/26/2006 9:43:04 PM:
If you can tolerate a moderate hill, the Hamburg trail is a nice ride. You can access the trail from the parking lot of the cemetery that's across 94 from Francis Howell high school. There is a gate there that puts you right on the trail. The trail goes past the Weldon Spring cleanup area and mound all the way to the KATY trail between the Weldon Spring and Defiance trailheads. It's about 5 miles from the cemetery to the KATY. There is a 6% grade at one point that you must climb on the return trip to the cemetery. It's not too bad on a mountain/comfort type bike with low gearing.
Once you hit the KATY, your options are pretty much open. From the Cemetery to Klondike park and back is 26 miles. There is a pretty tough hill to climb from the KATY up into Klondike park, but the park is worth it.
You could always park at the Page bridge lot and take the KATY either direction.
There's also a paved bike path between Laurel Park and the St. Peter's Rec-Plex. I'm not sure about the distance between them, but it can't be more than 4 or 5 miles. It's an easy ride.