Frijoles canyon... looks like they were busy for a while!
Right near Los Alamos. Beautiful area, worth a visit, esp in Spring or Fall when you won’t have to wait for parking. The Tsankawi section is great to tromp around on. Lots of cavates carved into the volcanic tuff (which is what that photo displays). The particular one in the photo is called Long House in Frijoles Canyon, just up the trail from Tyounyi. I did quite a bit of research work in that area.
LA has a nice museum on the Manhattan Project and development of atomic/nuclear energy. LANL also has some nice sites that I’ve been to, but they are not normally open to the public.