Montezuma Castle’s Sinagua farmers built a structure large enough to house 35 people high on a steep canyon wall in stages. Before the castle was built, limestone ledges and caves were present. The first construction was a six-room unit on the 3rd floor. A small room was then added at the west (left) end, and one room was built on the next, 4th, floor. The 4th floor was expanded, and two rooms were built in a small cave on the 2nd floor. A parapet and two rooms were then built at the top on the 5th floor, along with three small rooms at the front on the 1st and 2nd floors. Finally, three stacked rooms formed the central “tower” on the 1st, 2nd, and 3rd floors, while small storage rooms may have been built earlier.