The Mar y Sol Pop Festival (also referred to as Mar y Sol Festival or simply Mar y Sol – Sea and Sun) was a rock festival that took place in Manatí, Puerto Rico, about thirty miles west of San Juan, on April 1–4, 1972. It was held on 420 acres (1.7 km2) of countryside adjacent to Los Tubos beach in Manatí on the north shore of the island. An estimated 30-35,000 people attended the festival. Several accidental deaths at the beach and a murder were also damaging to the festival's reputation.