Mary's Loop starts with a solid climb up a rocky dirt road and is not an inviting start. You might look at this from the road and doublecheck the trail sign... but it gets better - much better!
Mary's is one of the classics in the area - partly because the ride itself and the scenery are excellent, and partly because it's the main connector between the other awesome rides here.
You'll soon hit the canyon rim with great stops along the way to take in the massive views overlooking the Colorado river. The doubletrack gives way to singletrack and it gets more technical and rocky in spots. Some riders will need to walk a couple of very short bits.
The trail intersects with the Horsethief Bench
Loop, Mary's Cutoff
, and Wrangler
Loop (Horsethief Bench
Loop is well worth a detour, or at least watching someone trying to ride the entrance "hike-a-bike").
Then there's more riding along the rim, with no real climbs but several short technical sections. After the intersection with Steve's Loop
(again, well worth a detour), the trail becomes doubletrack again, turns away from the rim, and generally gets less interesting.
You could turn around here or continue another 1.5 doubletrack miles to finish off Mary's Loop when it ends at Lion's Loop