Andaman & Nicobar Islands
Island-hop between the Andaman's diverse islands by government ferry or private speedboat — Neil Island (coral reefs and laid-back beaches), Ross Island (abandoned British capital being reclaimed by jungle), Baratang Island (limestone caves and mangrove creeks), and Little Andaman (most remote; bioluminescent plankton beaches) each offer unique experiences.
The Baratang Island trip (accessible only through a Jarawa Tribal Reserve — vehicles convoy with police escort) to the limestone cave is a uniquely surreal and restricted-access experience. Permits required.