This building is so named due to finding a vaulted tomb in its interior, unique in San Gervasio. The structure is a platform, since it had no building on top of it, only benches and an altar, it is believed that the structure was used for open air ceremonies in which not only the priests participated but also the congregation in the plaza. The structure has two construction periods, the first one was built during the Terminal Classic period (1000-1200 a.d.) and the later one during the Post Classic period (1200-1650 a.d.)