It sits on a platform 8 to 12 m high, 1087m long and 1.70m wide; it was divided into 3 parts separated by very tall transverse vaults. Its façade boasts the most beautiful examples of Mayan sculpture and architecture.
Masks of the god Chaac adorn its four corners and are also arranged diagonally forming a serpentine molding. In the center stands out the throne of a majestically seated sovereign, surrounded by entwined serpents and masks of the god Chaac. It dates from 900-1000 AD.