Maybe you've read Stephen King's huge fantasy epic "The Dark Tower", or perhaps the Tower of Mordor from "The Lord of the Rings" more readily comes to mind? In any case, you'll be surprised to find the fantastic huge black tower actually exists... on a small island near Africa. More precisely, in the Obo National Park on the São Tomé island in the Gulf of Guinea. It's called Pico Cão Grande, or the Great Dog peak.
This is one of the highest needle-shaped "volcanic plug" peaks on Earth (300 m), perhaps even more impressive than the Devils Tower in Wyoming (386 m), as it rises above the landscape in an equally unexpected and even bluntly obscene way. It will be however more difficult to photograph than Devils Tower : its top is often hidden by clouds or precipitation, not to mention that it's harder to get to the tiny country of São Tomé and Principe.
The heavy mist and humidity over the surrounding jungle (the rainfall varies between 4500 mm to 5000 mm per year) adds to the mystery and the foreboding feeling of the Great Dog Peak, as its rocky presence rises and darkly glistens in the murk.