Polihale State Park

"Your rental car contract will prohibit you from accessing this beach—and should you attempt it, you'll understand why. The road is terrible, but the beach at its end is incredible. At 17-miles long, its one of Hawaii's longest beaches and it is vast and stunning and more or less empty. It abuts the Napali Coast and shares those epic views. Similarly, it faces the open ocean and the waves are intense, making the water only safe for strong swimmers. Most visitors come to walk the beach."