Miami's beaches stretch for miles along the barrier islands that separate Biscayne Bay from the Atlantic. South Beach gets the crowds and the fame, but the sand improves as you head north — Mid-Beach and Surfside are wider, quieter, and just as pretty. Key Biscayne, across the Rickenbacker Causeway, has two excellent beach parks: Crandon Park with its calm, shallow water, and Bill Baggs Cape Florida State Park at the island's southern tip, with a historic lighthouse and some of the best snorkeling accessible from shore.