Lake Toba — The largest volcanic lake on Earth

The Lake Toba (Danau Toba) is the largest volcanic lake in the world—100 kilometers long, 30 kilometers wide, and up to 505 meters deep. It was formed about 74,000 years ago during the most massive volcanic eruption of the last 2 million years: The eruption of the Toba supervolcano ejected so much ash into the atmosphere that a years-long "volcanic winter" followed, possibly reducing the world population to a few thousand people.

Today, the lake is a place of silence and beauty: Crystal-clear water, surrounded by forested mountain slopes, with the mild climate of the high altitude (905 meters). In the middle lies Samosir—an island almost as large as Singapore, raised from the lakebed by volcanic activity. Samosir is the heart of the Batak culture.

The Batak — Sumatra's fascinating people

The Toba Batak are one of Indonesia's most fascinating peoples: predominantly Protestant Christians (a legacy of German missionaries in the 19th century), known for their distinctive wooden houses with upward-curving saddle roofs, their lively music, and—historically—for cannibalism, which was practiced until the 19th century.

On Samosir, you will find cozy guesthouses directly on the lake in Tuk Tuk (the main tourist town), bathing beaches, and a relaxed rhythm. The Stone Chairs of Ambarita (an old Batak meeting place with the infamous execution stone), the Royal Tombs of Tomok, and the Siallagan Village with traditional architecture are the cultural highlights.

The best way to experience the lake: Rent a motorbike and circle Samosir (about 3–4 hours). The east side is wild and little visited, with hot springs and spectacular views.