Mary's Loop starts with a solid ascent up a rocky dirt road and is a classic in the area - partly because the trail itself and the scenery are excellent, and partly because it's the main connector between other beautiful trails.
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 rugged and rocky in spots.
The trail intersects with the Horsethief Bench Loop
, Mary's Cutoff
, and Wranglers Loop.
After, there's more running along the rim with no major ascents but generally rugged terrain. 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 miles to finish off Mary's Loop when it ends at Lion's Loop