Sistema Sac Actun (from Spanish and Yucatec Maya meaning "White Cave System") is an underwater cave system situated along the Caribbean coast of the Yucatán Peninsula with passages to the north and west of the village of Tulum. Exploration started from Gran Cenote 5 kilometers (3.1 mi) west of Tulum. The whole of the explored cave system lies within the Municipality of Tulum (state of Quintana Roo).