Cape Cod National Seashore extends some 40 miles around the curve of the Outer Cape and encompasses the Atlantic shoreline from Orleans all the way to Provincetown. Under the auspices of the National Park Service, it's a treasure trove of unspoiled beaches, dunes, salt marshes, nature trails and forests. Thanks to the backing of President John F Kennedy, this vast area was set aside for preservation in the 1960s, just before a building boom hit the rest of his native Cape Cod.
Access to the park sights is easy: everything of interest is on or just off MA 6. The year-round Salt Pond Visitor Center in Eastham is the place to start. The Province Lands Visitor Center in Provincetown is smaller and open seasonally, but it has similar services to the Eastham center plus a fabulous ocean view.
Beach parking permits cost $20 per day or $60 per season and are valid at all National Seashore beaches, so you can use the same permit to spend the morning at one beach and the afternoon at another; pedestrians and cyclists pay $3, motorcyclists $10. The fees are collected only in summer – from late June through early September, when lifeguards are on duty – and on weekends and holidays from Memorial Day (late May) to the end of September. Outside these times, beach parking is free.