Las Columnas shapes part of the outer perimeter of the Central Plaza, the hub of governmental activities from 1200 AD until San Gervasio was abandoned. The columns supported a mortar roof when it was built in the Early Post Classic period (950 – 1200 AD). Inside the stone structure archeologists found several skeletal remains encased in ceramic jars. Most were pre-Columbian. Other crypts contained Spanish beads suggesting they dated from the 16th century. Juan de Grijalva was the first Spaniard to visit here in 1518.