Lake Nyos

Lake Nyos fills a crater in the volcanic highlands of the north-west, and on the night of 21 August 1986 the carbon dioxide that had accumulated in its deep water came out of solution and rolled down the valleys as a dense cloud, suffocating around one thousand seven hundred people and their livestock in the villages below. It was one of a very small number of recorded events of this kind. Since 2001 vertical pipes have been installed to draw deep water to the surface and vent the gas continuously, and monitoring continues. The lake itself is a still, blue-green sheet of water in a steep crater, and the valleys below it were emptied of people for many years.

What you actually see

• The degassing pipes - vertical columns venting gas from the deep water.
• A steep-walled crater lake - still water in the volcanic highlands.
• The valleys below - the ground the gas cloud moved through.
• Continuous monitoring equipment - the instruments watching the lake.

When to go

November to February in the dry season, when the track is passable. A day. Local permission and a guide are needed, and the site should be approached as a place where a great many people died.

Honest expectations

This is the site of a disaster in living memory and villagers nearby lost families; visitors are expected to behave accordingly. The track in is rough and needs a capable vehicle. There are no facilities. Ask people on the ground how things stand before you travel.

Nearby

Wum is south-west; the North-West highlands surround it.