The bather went missing at a beach in the popular tourist town of Salou, Catalonia, early on Saturday morning.
Emergency rescue services received a call at 6:45am, as one swimmer had reportedly not emerged from the water after he went bathing with friends.
According to teinteresa.es, a major search and rescue operation was immediately launched. This included a helicopter Helimer 201, and rescue boats along with various local Catalan police units.
After a massive three-hour sea rescue operation, local police agents eventually spotted the individual at 9:38am, relaxing at a nearby beach bar.