The Twenty Mile Wash Dinosaur Trackway can be found in the Grand Staircase-Escalante National Monument along the Hole-in-the-Rock Road.
First of all, let me say the tracks are difficult to find and will be unimpressive to most casual observers. We’ve seen a lot of dinosaur trackways in Utah, and this was the least impressive of them. These tracks are faint sauropod tracks with no toe marks. They look more like faint impressions in the rock. That being said, this is one of the largest dinosaur trackways in the world with over 800 individual tracks.
To access the trackway, turn off the Hole-in-the-Rock Road at mile 14.3 onto a road called Collet Top Road. This road is generally accessible to most 2WD vehicles, but high-clearance is recommended. Once you get on Collet Top Road follow for 2.4 miles until a small, two track road branches to the right. Turn right and head toward the gray/white sandstone. If the wash looks impassable after 0.2 miles on this road, you will need to park here and walk north to the sandstone rocks. We were able to drive down this road until we came to a small sign that marked the trail. We did drive around for a bit until we spotted the small sign, but there aren’t too many places to go in this area. There is a trailhead registry at the base of the white slickrock. You’ll be climbing to the top of this low slickrock rise to find the tracks.
We only found one really beautiful track. It was very clear, but it would be impossible to describe it’s location to you. I’ll try anyway. It is directly up the hill from the register back against where the second rise in the slickrock begins. Good luck finding it, though. Look instead for shallow but regularly spaced impressions across the slickrock top.
We did stop at the Escalante visitor center for information on these tracks. They gave us a paper to help find the location and showed us a picture of the tracks, which helped a little bit. So we recommend stopping for a little more clarification at the visitor center. Happy tracking!