On the sides of the Templo Mayor, archeologists have excavated a number of palatial rooms and conjoining structures. One of the best preserved and most important is the Palace (or House) of the Eagle Warriors. This area dates back to the fourth stage of the temple, around 1469. It was excavated in 1981 and 1982 by José Francisco Hinojosa. It is a large L-shaped room with staircases decorated with sculptures of eagle heads. To enter this main room, one had to pass through an entrance guarded by two large sculpted representations of these warriors. The Eagle Warriors were a privileged class who were dedicated to the god Huitzilopochtli, and dressed to look like eagles. Adjoining this palace is the temple for these warriors—also known as the Red Temple. This temple shows clear Teotihuacan influence in its paintings (mostly in red) and the design of its altar. Almost all the interior walls of the House of the Eagles are decorated with beautiful paintings and contain long benches, which are also painted. These benches are composed of two panels. The upper one is a frieze with undulating serpents in bas-relief. The lower panel shows processions of armed warriors converging on a zacatapayolli, a grass ball into which the Mexica stuck bloody lancets during the ritual of autosacrifice. This palace specifically imitates much of the style of the Burnt Palace, located in the ruins of Tula.