Muyil / Chanyaxche
This small ruin is known by two names: Muyil or Chanyaxche. It is just down the road from the Tulum ruins but is much more quiet, so you can tour at your leisure. Muyil was a trading post for the ancient Mayan people and the structures at the site date from 1100-1200 AD.
One interesting feature here is the unique round tower on top of “El Castillo.” Admission is free on Sundays, so make your plans accordingly.
Location: 15 min drive S of Tulum ruins, Tulum
Visit their site fore more information.