Carbon Trail is a fairly rocky, loose and difficult trail that either starts or ends out near Ohio Pass road depending on which direction you are going. The particularly rocky and loose nature of this trail makes parts of the climb a hike-a-bike or the downhill not particularly great. It does however, make it a great alternative as an adventure ride loop by riding up Carbon, riding Para Me Y Para Te Trail and down Green Lake Trail. This ride is tough, but you'll at least be given a sweet downhill with Green Lake Trail.
This is one of the only trails around this area that allows motos, therefore yield when necessary.