From swimming with sharks in Belize, to a seaside cascade in Costa Rica, to kitesurfing in the Caribbean and four-wheeling in South Africa; thrill-seekers explore the world's most top-secret swimming holes.

From a canyon full of black water and a waterfall buried deep in the rain forest to an exotic animal safari leading to a secret beach; some of the planet's best-kept secrets.

The pristine waters known only to the locals in the Dominican Republic, Utah, Easter Island and Hawaii.