Palenque’s palace is one of the Maya world’s most compelling and impressive complexes. Built atop a platform 10 meters (33 feet) high and covering an area larger than a city block, it is composed of thirteen vaulted “houses,” four enclosed patios, and three spacious underground arcades. It was built in phases over the course of nearly four centuries, and served as residential quarters for the city’s elite and as an exclusive administrative and ceremonial center.

The iconic tower is singular in Maya architecture—only a handful of minor tower-like structures even compare—and archaeologists have speculated that it was built to provide a ceremonial observation point of the winter solstice (December 22), when the sun appears to drop directly into the Temple of the Inscriptions. It may also have been used to make astronomical calculations, an important part of Maya religious rites, or simply as a watchtower.

Unfortunately, the top of the tower had collapsed by the time it was rediscovered, so the structure’s original height and appearance—and therefore function—could only be guessed from the pattern of rubble.

Two sunken patios on the palace’s northern half are each dedicated to a different purpose. The Patio of the Captives, in the northeast corner, contains large stone panels depicting important prisoners captured in war; notice how each has his hand on the opposite shoulder, a common gesture of submission. In the northwest corner, the smaller Patio of Warrior Chiefs is believed to have served as a meeting place for military leaders. Pillars facing into this patio have remnants of stucco moldings depicting figures in elaborate militaristic regalia.

The southern half of the palace is more residential and ceremonial in nature, with enclosed rooms and small tidy patios. In the southwest corner, two holes marked with notched stones probably served as toilets, and are connected to a surprisingly sophisticated drainage and plumbing system built beneath the stone floors. It still works, too—after heavy rain, maintenance works sweep standing water into the holes to drain it out. Also look for a narrow flight of stairs leading down into a maze of underground rooms that likely served as royal sleeping quarters.

Dividing the southwest and southeast sections is the palace’s most notable temple, the Casa de Ascensión de Poder (House of Enthronement). It was here that Palenque’s supreme ahau (high lord or kings) were officially throned, likely in elaborate ceremonies attended by a small cadre of religious, military, and political leaders. On the western exterior wall is the Oval Tablet, which depicts the city’s best-known ruler, Pakal the Great, receiving the insignias of power from his mother in A.D. 615. Also look for paintings of flowers on the same wall—they’re originals.

Even the palace’s exterior facades are fascinating, and easy to miss while exploring the labyrinthine interior. The West Gallery, atop a long bank of stairs facing the main plaza, has six stout pillars, four of which are still decorated with large stucco reliefs. A plaque at one end describes what’s depicted there, including a man holding a serpent and dancing with a woman dressed in a traditional huipil and an incarnation of Chaac, the god of rain, decapitating captives.

The East Gallery has similarly elaborate relief carvings, including several circular frames that probably contained images of assorted gods (but which were destroyed or looted long ago). A dramatic triple-layered vaulted archway leads into the Patio of the Captives.