Try this 13.1-mile out-and-back trail near Silverton, Colorado. Generally considered a challenging route. This is a popular trail for backpacking, birding, and camping, but you can still enjoy some solitude during quieter times of the day. The best times to visit this trail are May through October. Dogs are welcome and may be off-leash in some areas.
https://www.alltrails.com/trail/us/colorado/engineer-mountain-trail--3
Length: 13.1 miles
Elevation Gain: 3024 feet
Route Type: Out & Back
*Photo credits to All Trails*