Annobón is a volcanic island

— Erick Tyson von Mueller

Annobón island is formed by a volcano in the Cameroon line of volcanos rising from the sea floor out of the waters of the Gulf of Guinea. Some time ago the volcano erupted in a great explosion to form a caldera, or crater, where the top of volcano had been.

Don’t worry, the volcano is extinct.

Now the highest point is the peak, Quioveo, at the center of the island. The height is 598 meters (1,962 ft). Dare you try to climb it? There will be no means to rescue you if you need help up there.

Quioveo rising above the mountain, from San Antonio de Palé
View of the Quioveo rising above the mountain, as seen from San Antonio de Palé. Image: TripAdvisor
Quioveo rising above the mountain, from Hotel Annobón
Another view of Quioveo rising above the mountain, as seen from Hotel Annobón. Image: TripAdvisor

Over time, this caldera collected water to form a lake called Lago a Pot. So, lago means lake in Spanish and Portuguese. What about pot? Perhaps the caldera is like a pot that collects the water, but I was taught that the Spanish word for pot is olla.

The lake inside of the volcano
Lago a Pot, the lake inside of the volcano, as seen through a clearing in the surrounding jungle. I give the mist-shrouded composition 5/5. Image: TripAdvisor

They say the surface of the lake 284 meters above sea level.

They also say that radioactive and/or toxic waste was dumped in the lake Lago a Pot in the 1990s. The lake is in a caldera, which means that the bed of the lake, beneath the sediment, is the remains of a magma intrusion up through the overlying crust. The composition of these remains could contain minerals bearing heavier radioactive elements from the mantle, or minerals that leech into the water making it toxic, if, indeed, the lake water is radioactive and/or toxic.