Float in the Pedra de Lume salt crater

Sail through a narrow gap into the flooded caldera of an active volcano, past a ruined whaling station and beaches warm enough to dig a hot bath.

Climb the islands' active volcano.

Deep-blue volcanic crater lake ringed by weekend cafes and piers.

The world’s largest volcanic lake, with Batak villages on Samosir Island at its centre.

Active volcano with a huge summit crater.

Geysers, hot springs and Maori culture.

Soak in a naturally warm pool on an uninhabited island, icebergs drifting past.

Swim with the wild pigs of Big Major Cay.