Rutland Island

Closeness is the argument for it: 20 km south of Port Blair, which by the standards of this archipelago counts as next door, and it belongs to the South Andaman district. That short crossing is the reason to consider it at all, because the record says nothing about what waits when you land. Go with a boatman who knows the coast and without fixed expectations. It is the sort of place that rewards curiosity and punishes a timetable.