Lost Valley

Lost Valley

The name comes from the bootleggers who once made use of the area, getting lost among the numerous hollows. It was also near the site of an ammunition works and uranium processing plant which necessitated the cleanup that lies under the large mound on Hwy. 94. Now, the trail is a 10.5 mile loop with a mixture of double and singletrack punctuated with old homesteads, rock formations, natural springs, and a waterfall crossing. This is a very scenic and enjoyable mountain bike experience.

The gravel/doubletrack sections are fairly flat. The singletrack sections are super-flowy with punchy rock obstacles that will reward you with great views and better riding, the trail can get technical in spots and is now a much longer ride due to the increased singletrack. Be advised that this 10.5 mi loop will take some riders 2 hours to navigate due to the amount of singletrack and the difficulty of the rocky sections.  There is a central fire road that cuts the loop almost in half which can be used to shorten or lengthen your ride.

Trail surface varies from dirt to rock throughout the trail, and drains very well, except in the flats of the lower creek bottom.

The trail is open until 10 pm, so it's a good place to ride at night.


From the Highway 40/94 interchange: Take Highway 94 South approximately 5 miles. The trailhead parking lot will be on your right hand side. It is not very well identified as "Lost Valley". A good landmark is the shooting range at the top of a hill on the right hand side of Hwy 94. When you descend that hill the parking lot will be on your right hand side, at the very bottom. It can also be accessed by going 7.2 miles east on the Katy Trail from Klondike Park.

Trail Information




10.5 miles




Trail Conditions

Latest Conditions

From perfessrgary on Sun, 02/23/2020 - 9:05pm - Lost Valley (St. Charles Area)
Rode late morning/early afternoon. Cedars was a bog, Rest has a few spots.
From rmhchs on Sun, 02/23/2020 - 9:50am - Lost Valley (St. Charles Area)
Thaw condition is in full swing . . . rode this am . . . just too much mud . . . the kind you sink in about an inch and almost impossible to avoid.
From rmhchs on Fri, 02/14/2020 - 5:11pm - Lost Valley (St. Charles Area)
Trail Race tomorrow at 8am on Lost Valley Trail . . . single track and fire road
From WeekendRider on Fri, 02/14/2020 - 1:12pm - Lost Valley (St. Charles Area)
Trail is perfect but I’m not gonna lie it’s freaking cold brrrrrrrr. Come get sum if you like your balls to shrink :D
From rmhchs on Sat, 02/08/2020 - 1:38pm - Lost Valley (St. Charles Area)
Wet in spots but rideable . . . snow covers entire woods and about 5% of trail. Scenic ride. . . Need to clean bike afterwards.
From rmhchs on Fri, 01/31/2020 - 6:48pm - Lost Valley (St. Charles Area)
Of the 7 miles from the lower lot to the service road . . . 5.5 miles are good . . . about 1.5 miles are squishy BUT tires do NOT pick up any mud. . . definitely have to clean off bike when finished but no mud on chain.