Mount Longonot, a dormant stratovolcano rising 2,776 metres above sea level, is the most visible landmark in this part of the Rift Valley. From the Naivasha area you can see it clearly to the southeast, its symmetrical cone rising above the flat valley floor. The hike to the crater rim and around it is one of the better half-day walks available from Nairobi without a long drive.
The trail starts from the park gate and climbs steeply up the outer cone — a 2–3 hour ascent for most walkers. The rim circuit adds another 2–3 hours, taking you around the edge of the caldera with views in every direction: down into the forested crater on one side, across the Rift Valley with Lake Naivasha glinting below on the other. Buffalo and other large animals do use the crater forest, so the park requires you to go with a ranger.
The gate is about 8 kilometres south of the main Nairobi–Naivasha highway, signposted near the village of Longonot. Matatus pass the junction; from there you need to walk or arrange a boda-boda. Start early — the descent in afternoon heat is unpleasant and afternoon cloud can obscure the views.