Nunnery Quadrangle antique ruins, the Cuadrangulo de las Monjas, West wall, Uxmal ruins Mayan archeological heritage site in Yucatan, Mexico. The Nunnery Quadrangle in Uxmal was built from 900-1000, and the name related with nuns was assigned in the 16th century because it resembled a convent. The quadrangle consists of four palaces placed on different levels that surround a courtyard. The eastern building (photographed here) has a length of 50m with five chambers, two of which have other interior rooms. The decoration of its walls mimics snake scales complemented by six groups of double-headed snakes arranged from the largest on the top, to smallest on the bottom and with owl heads, a bird associated with death. Chaac’s masks are also present on both edges.