Sipiso-piso Waterfall

Sipiso-piso means like a knife, and the fall is a single narrow column dropping about a hundred and twenty metres off the northern rim of the Toba caldera - the water comes from an underground river inside the volcanic plateau and emerges at the lip, which is why it runs in a steady thin stream rather than spreading. From the viewing area on the rim you look down the fall and, in the same frame, along the whole northern arm of Lake Toba with the Karo plateau behind, which is why this is the standard photograph of the region. Some six hundred steps descend to the base, a hard climb back in the heat. Tongging village sits on the lake below. The caldera itself was formed by the eruption of about seventy-four thousand years ago, among the largest known.

What you actually see

• A 120-metre knife of water - fed by an underground river emerging at the rim.
• Lake Toba in the same view - the northern arm of the caldera below.
• Six hundred steps down - to the base of the fall and back up.
• The caldera rim - the edge of one of the largest known eruptions.

When to go

All year; mornings before the cloud. Half a day.

Honest expectations

The climb back from the base is hard in the heat and takes far longer than the descent. The rim area is crowded with stalls and touts. Flow drops in a dry spell.

Nearby

Tongging is on the lake below; Berastagi and Sibayak are north.