A local history museum in the center of Aztec with a decent collection of Ancestral Pueblo artifacts and exhibits on the area's Anglo pioneer and oil boom history. The Pioneer Village section is a cluster of reconstructed historic buildings — a schoolhouse, blacksmith shop, and general store — that give a sense of what the San Juan Basin looked like in the early 20th century.
Modest in scale but well-maintained, and a useful complement to the National Monument if you want context beyond the archaeology. Budget an hour. The museum also has a small gift shop with books on regional history and Native cultures of the Four Corners area.