Basin. Its rectangular shape and design is related to the Pueblo II cultural group, rather than the Pueblo III style or its Chacoan variant. It contains 55 rooms, four ground-floor kivas, and a two-story cylindrical tower that may have functioned as a kiva or religious center. Evidence of an obsidian-processing industry was discovered near the village, which was erected between 1125 and 1130. Pueblo Alto is a great house of 89 rooms located on a mesa top near the middle of Chaco Canyon, from Pueblo Bonito; it was begun between AD 1020 and 1050 during a wider building boom throughout the canyon. Its location made the community visible to most of the inhabitants of the San Juan Basin; indeed, it was only north of Tsin Kletzin, on the opposite side of the canyon. The community was the center of a bead- and turquoise-processing industry that influenced the development of all villages in the canyon; chert tool production was common. Research at the site conducted by archaeologist Tom Windes suggests only a handful of families, perhaps as few as five to twenty, lived in the complex; this may imply that Pueblo Alto served a primarily non-residential role. Another great house, Nuevo Alto, was built on the north mesa near Pueblo Alto; it was founded in the late 12th century, a time when the Chacoan population was declining. Outliers Another cluster of great houses lies in Chaco's northern reaches; among the largest is Casa Chiquita ("Small House"), a village built in the 1080s, when, in a period of ample rainfall, Chacoan culture was expanding. Its layout featured a smaller, squarer profile; it also lacked the open plazas and separate kivas of its predecessors. Larger, squarer blocks of stone were used in the masonry; kivas were designed in the northern Mesa Verdean tradition. Two miles down the canyon is Peñasco Blanco ("White Bluff"), an arc-shaped compound built atop the canyon's southern rim in five distinct stages between 900 and 1125. A nearby cliff painting (the "Supernova Platograph") may record the sighting of the SN 1054 supernova on July 5, 1054. Hungo Pavi, located from Una Vida, measured in circumference. Initial probes revealed 72 ground-level rooms, with structures reaching four stories in height; one large circular kiva has been identified. Kin Nahasbas, built in either the 9th or 10th century, is sited slightly north of Una Vida, positioned at the foot of the north