Interior view SE of the great kiva at Chetro Ketl Pueblo, Chaco Canyon, New Mexico: a circular, subterranean room used by the Anasazi for religious ceremonies. The four stone-lined circular holes held roof pillars of ponderosa pine seated on circular sandstone pads. The centre may have been open to allow smoke from the square firebox to escape. The pair of rectangular 'earth vaults' may have been covered by planks to form foot drums or used for the ritual sprouting of corn, beans and squash. A stone bench encircles the room and two phases of walling are visible. The niches had been carefully sealed with stone and each one contained a shell and turquoise necklace: a total of over 17,000 beads in strings up to 17 feet long.