Coba () is a big ruined city of the Pre-Columbian Maya civilization. It is in the state of Quintana Roo, Mexico. It is about 90 km east of the Maya site of Chichen Itza, about 40 km west of the Caribbean Sea, and 44 km northwest of the site of Tulum. Coba was thought to have had around 50,000 people living in it.