Syncline Loop is a demanding trail from the Upheaval Dome trailhead in Canyonlands. The loop runs about 8 miles, following washes around the dome and dropping toward the Green River side of the Island in the Sky district.
It is a serious desert hike, not a casual viewpoint stroll. Expect rough footing, heat, and significant elevation change, and carry enough water even though the north side of the loop can have shade and seasonal water.