This was a really great hike! The landscape was always changing so the hike stayed exciting- downhill and uphill portions, views of the old mines, the arch, and then the final beautiful view overlooking the Colorado River.
I agree with the other reviews that this hike is moderately strenuous. There were some tougher uphill parts that left me a little winded, but the uphill parts were quickly followed by flat or downhill portions.
The only tricky part of this hike is finding the trailhead. We knew we needed to make a right at some point (Norm K. said it was about 9/10 of a mile into the wash) but we saw a cairn less than half a mile in, and we decided to go that way. It looked like a path a first, but then the path kind of ended, so we somewhat forged our own. Luckily we ended up in the right place, but it was very unclear for a while. On the way out we followed the path that led us further into the wash. So it looks like you can take either trailhead, but the first one is not as clearly marked along the way.
If you want a decent length hike (6 miles) with great views, then check this out!