The Palace, a complex of several connected and adjacent buildings and courtyards, was built by several generations on a wide artificial terrace during four century period. The Palace was used by the Mayan aristocracy for bureaucratic functions, entertainment, and ritualistic ceremonies. The Palace is located in the center of the ancient city. Within the Palace there are numerous sculptures and bas-relief carvings that have been conserved. The Palace most unique and recognizable feature is the four-story tower known as The Observation Tower. The Observation Tower like many other buildings at the site exhibit a mansard-like roof. The A-shaped Corbel arch is an architectural motif observed throughout the complex. The Corbel arches require a large amount of masonry mass and are limited to a small dimensional ratio of width to height providing the characteristic high ceilings and narrow passageways. The Palace was equipped with numerous large baths and saunas which were supplied with fresh water by an intricate water system. An aqueduct, constructed of great stone blocks with a three-meter-high vault, deviates the Otulum River to flow underneath the main plaza. The Palace is the largest building complex in Palenque measuring 97 meters by 73 meters at its base.