Coronado cave
Coronado Cave (31°21′4″N 110°15′38″W) is located on the Coronado National Memorial in Cochise County in southern Arizona near the Mexican border. Walking in the cave is rather easy and the temperature is consistent. Some rooms require crawling in order to enter. The cave has both stalactites and stalagmites. The cave has been measured to be approximately 600 feet long, 70 feet wide and 20 feet tall with several passages and crawl ways.
Cave data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).