Kiva is a Hopi word for ceremonial room. The kivas at mesa Verde were underground chambers that may be compared to churches of later times. Based upon modern Pueblo practice, Ancestral Puebloans may have used these rooms to conduct healing rites or to pray for rain, luck on hunting, or good crops. Kivas also served as gathering places, and sometimes as a place to weave. A roof of beams and mud covered each kiva, supported by pilasters, Access was by a ladder through a hole in the roof. The small hole in the floor is a sipapu, the symbolic entrance to the underworld.