Nude sunbathers. Kaihalulu Bay on Maui near the town of Hana is home to a unique red sand beach. Towering red cinder cliffs surround the bay, and the blue ocean swirls along the red sandy shore.

The combination of the black sand — the result of volcanic rocks that have eroded and weathered over time — and the clear blue waters of the Atlantic Ocean makes these beaches a dramatic and ...

Black magnetite sand covered a large portion of San Francisco's Ocean Beach on April 7, 2016. Amy Graff Black magnetite sand covered parts of Ocean Beach on April 5, 2016.

Punalu'u Beach. Photo: iStock. 3. Perissa Beach, Santorini, Greece. Santorini's whitewashed buildings and blue domes might steal the spotlight, but Perissa Beach proves the island has more to offer.