Warm sunset light on the sand, rock and water at Benagil Cave, Lagoa, Faro, Portugal

Skylit shore

Even amidst the many spectacular cliffs and sea caves that line southern Portugal’s Algarve coast, Benagil Cave is an eye-catcher. The cave was formed about 20 million years ago from the pounding waves that sweep in from the Atlantic. Rainfall has caused softer segments of limestone to erode, creating a giant hole in the cave’s roof, which is what we’re looking down through in our photo. The eye-shaped opening allows sunlight to stream into the cave, illuminating the golden beach and azure waters within its walls.