Aberdeen Loop is one of the longest trails at Hartman Rocks. It's usually ridden counter-clockwise, but can be ridden clockwise as well. If you're looking for the ultimate high desert cross country experience, this is your ride. It's a pretty far ride just to get to the loop from Bambi's, which makes the experience even better. Often times you'll have the whole trail to yourself as you meander through the remote feeling wide open sage country.
The trail itself isn't very technical which makes this a great long ride for intermediate riders.