Lake Poso

Danau Poso covers about three hundred and twenty square kilometres in central Sulawesi at around five hundred metres, and at over four hundred metres deep it is the third deepest lake in the country - an ancient lake, old enough to have generated its own endemic species, including several fish and a set of freshwater snails found nowhere else. Sidat, tropical eels, migrate down the Poso river to the sea to spawn and the young return upstream, and traditional eel traps, sogili weirs, were built across the river outlet for centuries; the construction of a hydroelectric dam on the Poso river has cut that migration and the effects on the eel population and on the fishing communities have been contested. Tentena at the northern end has the Saluopa waterfall nearby and Bada valley megaliths further south.

What you actually see

• A deep ancient lake - over four hundred metres, with endemic fish and snails.
• Eel migration and traps - the sogili weirs on the outlet river, now disrupted by a dam.
• White sand shores - unusual for a highland lake, at several points.
• Tentena - the lake town at the northern outlet.

When to go

May to September. Two days.

Honest expectations

Central Sulawesi saw serious communal violence around Poso in the early 2000s; the situation has been calm for years but travel advice for the wider region has at times been cautious. Facilities are basic.

Nearby

Saluopa waterfall is near Tentena; the Bada valley megaliths are south.