Part of the Colorado Trail (High Country) system.
Engine Creek Trail (FS#657) is part of a loop for mountain biking and hiking. Most mountain bikers start at the Molas Trailhead, get on the Colorado Trail, then ride the Colorado Trail/Engineer Mountain Trail to Engine Creek and exit at Cascade Creek, which takes you out to the Cascade turn at Hwy 550. Note that the signage is minimal in these locations.
If hiking: Getting to the trail from either end involves some preliminary hiking, therefore, an overnight stay may be helpful. There is a good central location and campsite at timberline where the trail starts down along Engine Creek, along with a beautiful view of Engineer Mountain and Jura Knob. Water is abundant, but purification is recommended to avoid problems with Giardia.