Mt Suswa is an extinct volcano in the Great Rift Valley, within sight of the more popular Mt Longonot. Located inside the community-managed Mt Suswa Conservancy, the mountain has caves that are home to a species of endangered bats.

Suswa’s caves consist of several floors of caverns and passages formed by volcanic activity that is still going on. The uppermost caves are easy to get to and only require a guide (hired from the conservancy), a good flashlight, and a stomach for dark enclosed spaces.

We entered the cave and walked into a large rocky vestibule with a tall ceiling and sandy floor. The last eruption is thought to have happened about 200 years ago; the lava that formed the caves marked the walls with multi-coloured designs, hanging stalactites and shapes that look like gnarled tree trunks.

Broken eggshells gave evidence of the birds that sometimes nest here. Some wet patches on the ground, our guide explained, were caused by water dripping from above, percolating through several metres of earth and rock for weeks after the rainy season.

Our torches came in handy as we were soon in total darkness. Thankfully, the passageways are wide and high enough to stave off claustrophobia.

Mt Suswa’s caves are one of only two known places in Kenya inhabited by the endangered large-eared, free tailed bats, with small populations recorded in Tanzania and western Uganda. They roost deep inside the caves during the day, and fly out at night to forage for insects.

Moving along we could smell the bats, or more precisely, the strong acrid odour of their urine. As we neared their chamber, we could hear their high, sharp squeals. Then we saw hundreds of them, huddled together high up and clinging to the rough walls. It was a fascinating sight.

The bats look like their name suggests. They are small bodied, with large, mouse-like ears and a short pointed tail.

The ground in the bat chamber is covered in a soft, fine sand almost like flour. It’s actually bat droppings, our guide informed us, that have accumulated over many years. I believed him because the odour now was particularly ripe, almost choking.

The bats quivered and squealed and didn’t seem to enjoy the light from our torches shining on them so we moved along after a short while.

From the bat chamber we walked to another cave with the interesting name of Baboon Parliament. It is a very tall grotto, the size of a concert hall, open on one side and with a hole in the ceiling where red roots of fig trees dangle almost to the ground.

The cave is favoured by baboons who come here to shelter from predators and the elements. Every evening they congregate in a noisy assembly much like our Members of Parliament. We did not see any baboons, but their signs were everywhere in the form of seed-filled turds scattered over the ground and rocks.

The Suswa caves make for a nice stopover on the way to other sites in the Rift Valley. We didn’t explore much more of the caves because our trip included hiking up the mountain and the day was already getting quite hot.

Our three-hour trek took us to the outer rim of Suswa’s double crater, a moderately challenging hike. Between the outer and inner rim is a wooded valley where Maasai pastoralists graze their cattle in the dry season. Tiny hot springs and steam vents puffing out of the vegetation show that there is still volcanic activity in the area.

The outer rim is a scenic spot for a picnic, with views of the inner crater covered in a pristine forest that is the abode of leopards, hyraxes and soaring eagles. Behind we could see Mt Longonot and Lake Naivasha in the hazy distance.

The scenic view from Mt Suswa of pristine forest that is the abode of leopards, hyraxes and soaring eagles. PHOTO | KAMWETI MUTU

Hiking around the entire crater takes eight hours, and although it is possible to combine a day hike with a cave visit, one is advised to arrive at the mountain early.

Alternatively, you can make it an overnight or weekend trip on one of the conservancy’s campsites. Booking a guide ahead of your trip is recommended, both for navigating the caves and because the trails are not well demarcated in some places.

From Nairobi, it’s about a two-hour drive down the Old Naivasha Road to the Mai Mahiu junction, where you turn onto the Narok Road and then branch off at the Suswa Conservancy entrance.