Floreana has three sites on the north coast. Post Office Bay has  had  a  barrel  that’s  been changed  many times, over the years. Whalers and Galapagos residents used this mailbox to leave their mail inside it, waiting for a captain of any boat headed to where the mail was addressed to deliver it. Very close-by is a pleasant swimming beach. At Punta Cormorant is a greenish beach, due to the accumulation of olivine crystal mineral. Sea lions swim and play around while you enjoy a good snorkel. The trail goes to a white sand beach, which is a nesting area for green turtles, stingrays (be careful) and white-tipped reef sharks swimming where waves crash, being visible from the shore. Devil's Crown is a half-submerged volcanic cone, considered to be one of the most outstanding marine sites of the Galapagos Islands.