Picture the stereotypical desert island: soft, white sand, luminous turquoise waters, coral reefs frequented by sea turtles and dugongs, and a densely jungle-clad, mountainous interior. Now add some charmingly dilapidated French-colonial architecture, a smattering of secluded resorts, and a few coracle-like basket boats bobbing on the shores, and you have the 16 tiny islands in the Con Dao Archipelago.

Con Dao today is as close to a desert-island paradise as we’ve found anywhere, but its beauty belies a dark past. From the 19th century, these islands were a place of exile for anti-colonialist (and later, anti-American) dissidents. Several of its prisons are now open to the public and offer a shocking insight into the abuses that occurred here until as recently as 1975.

Though its traumatic history casts a long shadow, it’s difficult to be sombre for long in such glorious surroundings. Hiking trails lead into the island’s untouched jungle interior, and the surrounding coral reefs offer some of the best diving in Vietnam. Meanwhile, 80% of the island is a protected national park, and the relatively undeveloped tourism scene means that its beaches are wonderfully quiet — fortunate for both visitors and the sea turtles who come to nest here from May to September.