This is Playa de Las Suecas, the only official nudist beach in Panama. It is located on Isla Contadora, which is part of the Islas Perlas archipelago. Easiest way to reach Contadora is by Air Panama flight from Albrook airport (8 seater plane, o/w about $25). You can also take a ferry-- two ferries run to the island, but the plane is easier and faster. There are 10 beaches on the island, but no ATMs, so bring cash. Suecas is signed to be nudist-- meaning you must go nude, but not everyone did.