Gila Cliff Dwellings - Shedding Light on the Mogollon Culture. For thousands of years, groups of nomadic people used the caves of the Gila River as temporary shelter. In the late 1200's, people of the Mogollon Culture decided it would be a good place to call home. They built rooms, crafted pottery and raised children in the cliff dwellings for about twenty years. Then the Mogollon moved on, leaving the walls for us as a glimpse into the past.