Forbes Traveler recently compiled their very own list of the top 25 sexiest beaches in the world. Most of them are in the Western Hemisphere for some reason and three of them are in the US (though only South Beach in Miami is part of the Lower 48). Two beaches in Hawaii also made the sexy cut: Ka'anapali Beach in Maui and Kauapea Beach on Kauai. Here's Forbes' description of Kauapea-
The so-called "secret beach" on the northern rim of the "Garden Isle" of Kaui isn't such a secret anymore. Curious tourists regularly stream onto its majestic span of white-gold sand, which offers nice views of the Kilauea Lighthouse. Access to the beach is fairly rugged--getting there requires 15 minutes of agile hiking--but funseekers continue to make the trek.