Santorini's beaches are shaped by its volcanic geology — most of the island's best beaches have black or red sand and pebbles rather than the white sand of other Cycladic islands. The southern coast has the main cluster of beaches, all within a few kilometres of each other and connected by walking or a short bus ride from Fira.
Perivolos and Perissa
The long stretch of black-pebble beach on the southern coast runs almost continuously from Perissa through Perivolos to Agios Georgios. Perivolos is the liveliest section, with sunbeds, water sports (jet skis, windsurfers, pedal boats), and beach bars. Perissa is slightly quieter. Frequent buses connect both to Fira.
Red Beach
Near the ancient site of Akrotiri, the Red Beach is Santorini's most visually striking. Towering cliffs of red and black volcanic rock rise directly from the water, and the coarse sand glows deep red in the afternoon sun. It's small and gets crowded; arrive early. The short walk from the road is worth it even if you don't swim.
Monolithos
The beach closest to the airport, Monolithos is a calm black-sand beach with gentle waves — good for families. It's less scenic than the southern beaches but also less crowded, with sunbeds, a children's play area, and a basketball court. Useful if you have an early flight or just want somewhere quieter.
Kamari
On the southeastern coast, Kamari is a proper resort town with a long promenade of bars and restaurants running alongside a black-pebble beach. Mesa Vouno, the rocky headland that separates Kamari from Perissa, rises sharply from the water at the southern end. Water sports are available and the beach is well organised with sunbeds and umbrellas.