I found a place to park off of paved Road 10 about 5.5 miles north of the marked road leading to Painted Hand Pueblo, and next to some old green tanks. Finding a reasonable place to park is one of the challenges in exporing these canyons. This area is north of the Hovenweep Visitor Center and also north of the Hovenweep outlying sites. I approached from the area near Lowry Ruins in the north part of the Monument.
In this area the paved road is very close to the canyon rim. I walked south along the canyon rim for about 0.25 miles, scanning the scenic area below for signs of any Ancestral Pueblo ruins sites. The view here is to the south toward McLean Basin.
There were some steep ledges in the area where I went down, but with gaps that allow a descent. The cows that graze here seem to be good route finders, and I was able to follow the cow trails to the canyon bottom, where, in the spring, a small amount of water was flowing.
On a later hike in the fall, I started at the same point and continued south down Ruin Canyon toward the junction with Cross Canyon. The west side of the canyon has a shelf area between the creek bottom and the cliffs on the west side. I went down canyon for about 2:00 hours, maybe 2.5 miles, to a point near a side canyon junction, well before Cross Canyon. On the down canyon hike I stayed closer to the cliffs and returned up canyon closer to the creek.
There aren't any trails in this area, but the walking through the Pinon Pine and Utah Juniper forest was reasonable. The going was slower than with a good trail. There were some large boulder areas near the cliffs where I noticed some pot shards and a small rock wall, but it didn't amount to very much. In the area where I turned around it looked like there was an old road approaching from the south that led to a drill hole with a pipe still sticking up. A short distance north of the drill hole I noticed a circular rock structure overlooking the creek, hidden in the trees.
I was lucky to see this small site as it isn't visible unless you walk right past it. The Ruin Canyon in this area seems to lack sagebrush fields that would have been farming fields and, in the fall, there wasn't much water flowing at the canyon bottom. I spent 4:30 hours on the second hike and revisited the two sites I had spotted earlier, plus the two more small ones.