As we crunched across the crater, Mtui shushed us and told us to stop.

A low growling noise was coming from one of the hornitos. A deep powerful vibration came from beneath our feet, as the volcano groaned and it resonated through everything. I wasn’t sure whether to stay where I was, continue walking or retreat to the rim.

Then we saw for the first time a small eruption, what looked like a spade full of soil jumping from the top of one of the hornitos.