After climbing Amasa Back there will be a jct. to the Pothole Arch trail which will take you to the start of Rockstacker. This is a very technical trail with a hike a bike entry. Only the very skilled will be able to ride it all. It can be done. I witnessed it. The "Red Line Trail" as it is refered to as by the locals, is very challenging as it rolls up and down across a slickrock bench towards Jackson's Trail. Only 1.7 miles in length, it feels so much more.
From Moab, drive south on Hwy 191 to Kane Creek Rd. (there is a McDonald's on the corner) turn right. The road will split shortly, stay left or straight and follow until road becomes gravel/dirt. From the gravel road (Kane Creek Rd.) drive to Amasa Back parking TH.
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