Is Mount Elgon a volcano?

Yes, Mount Elgon is the oldest and largest solitary volcanic mountain in East Africa.

The mountain is at least 24 million years old and has the broadest base of any free-standing mountain anywhere in the world. Volcanic activity remained for 14 million years. The caldera has a diameter of about 8 kilometer. Pleistocene activity created small crater lakes and hot springs inside the caldera.

Mount Elgon has five major peaks:
1. Wagagai (4,321 metres) in Uganda
2. Sudek (4,302 metres) on the Kenya/Uganda border
3. Koitobos (4,222 metres), in Kenya
4. Mubiyi (4,211 metres) in Uganda
5. Masaba (4,161 metres) in Uganda