The low, pyramid-like structures at this bell-shaped (thus campana) archaeological site date from as early as 1500 BC. They have been excavated since the 1930s and restored, along with a small shaft tomb with objects in situ and a ball court. The structures are oriented due north toward Volcán de Fuego, which makes for an impressive backdrop on clear days.
It’s about 3km north of Colima city and easily accessible by buses 7 and 22; taxis cost around M$50. A word of warning: wear good shoes and socks because there are lots of fire ants.