Walk the fabled breakwater, a 1.2-mile wall of flat-topped rocks that connects the town to Long Point beach. Jump off on either side to swim to the private, islandlike sand dunes (around a fifth of a mile). Follow the worn-in sand path until you hit the beach, which is often deserted in early morning and late afternoon. Continue a mile down the surf to Long Point lighthouse, a deserted, beautiful structure that juts up just before the sand tapers into the sea.
Take a twenty-minute stroll across the dunescape toward Herring Cove Beach, a gathering spot for Provincetown’s sizable gay community (but welcoming to all). Lounge on the beach and wait for high tide, when the winding marsh paths you've just crossed will be flooded by water. Then grab a float and explore the blissfully quiet temporary riverways, shielded from view by high reeds. Bring goggles to watch the crabs scuttling underfoot.
Drive northwest to the end of the Herring Cove parking lots, then hang a right onto the windswept Hatches Harbor. The huge swath of sand turns into a sparkling, twelve-foot-deep pool during high tide, when local kids (and daring adults) cannonball into the water.