Kerio Valley

The Kerio Valley is the long, hot trench that runs north through western Kenya between the Elgeyo Escarpment and the Tugen Hills, carrying the Kerio River down to Lake Turkana. UNESCO’s tentative list nomination for the irrigation system on its western wall puts the valley floor at 1,200 metres and the escarpment rising some 1,500 metres above it. Standing on the rim at Iten and looking across, the scale takes a moment to register.

It is one of the least-visited landscapes of this quality in Kenya, and it holds three things worth travelling for: a working thousand-year irrigation system, a small reserve with a remarkable elephant story, and some of the best paragliding air in Africa.

Where the Kerio Valley Is

The valley forms part of the western arm of the Great Rift Valley. Its western wall is the Elgeyo Escarpment, called the Marakwet escarpment along its northern stretch, with Iten sitting on the rim at around 2,400 metres and the Cherangani Hills rising behind. Its eastern wall is the Tugen Hills, with Kabarnet the main town on that side. The Kerio River runs the length of the floor and flows north, eventually entering Lake Turkana.

That places the valley across two counties, Elgeyo-Marakwet on the west and Baringo on the east, and it explains why the driving is slow: getting from one rim to the other means dropping well over a thousand metres and climbing back out again.

The temperature difference is the thing nobody warns visitors about. The rim is cool highland farming country. The floor is hot dry thorn country. The transition takes under an hour of driving and it is complete.

The Marakwet Furrows

The most significant thing in the Kerio Valley is not a view. It is a water system. Along the western wall the Marakwet have built and maintained an irrigation network of furrows that carry water from streams descending the escarpment out to fields that would otherwise be desert.

Kenya put the system on its World Heritage tentative list in June 2023, submitted by the National Museums of Kenya under cultural criteria (iii), (iv) and (v). The nomination describes irrigation along more than 40 kilometres of the escarpment, from south of Arror north to Tot, on the western side of the valley and onto the northern slopes of the Cherangani plateau in West Pokot. Two permanent rivers feed it, the Arror in the south and the Embobut further north at Tot. The furrows themselves are built from trunks, wood and stones laid on one another with the support of mortar and leaves, and from their sources they follow the weak and lower points of the ground, passing through hills and valleys.

What makes it remarkable is not the engineering alone but the governance. The nomination records furrows owned by clans, some co-owned, some shared on an annual rotation, with water borrowed between clans in drought and maintenance handled communally during whichever clan holds the furrow that year. A set of taboos has protected the system from destruction. UNESCO’s own text notes the furrows are under threat from the introduction of modern agricultural techniques on parts of the escarpment.

This is a living landscape rather than a monument, so visiting it means walking sections of the escarpment with someone from the community rather than arriving at a gate. See heritage tours in Kenya for how that kind of visit is usually arranged.

Rimoi, Kamnarok and the Elephants

Two small reserves protect parts of the valley floor, one on each side of the river. Rimoi National Reserve lies on the western bank in Elgeyo-Marakwet County; Kamnarok National Reserve lies opposite in Baringo County, around Lake Kamnarok. Elgeyo-Marakwet County Government gives Rimoi an area of 66 square kilometres, records it as created in 1983 to protect wildlife from poaching, and names groups of elephants as the main attraction alongside leopard, zebra, giraffe, impala and several hundred bird species, with a campsite in the bush beside Lake Kamnarok.

Elephants are what the valley is known for among Kenyan wildlife people. They move up and down it with the water and the browse rather than staying put, which means sightings are a matter of being there at the right time rather than of driving a circuit. That movement has also made human and elephant conflict a real and continuing issue in the valley’s farmland, and the fencing put up around the reserve was a response to it.

Neither Rimoi nor Kamnarok appears in the Kenya Wildlife Service conservation fee schedule, which covers national parks and the marine protected areas. Entry arrangements and charges for both are set locally rather than by the wildlife service, so they should be confirmed with the county before travelling rather than assumed from a national park band.

Paragliding Over the Kerio Valley

The escarpment generates thermals along its whole length and the valley is, by a distance, Kenya’s premier flying site. The Kenya Tourism Board describes numerous take-off points along broad escarpments covered in semitropical vegetation, a prevailing wind from north to south with a steady easterly flow that suits both launching and landing, and typical excursions of one to two hours covering ten kilometres or more.

The ceiling is a great deal higher than typical. The Paragliding Association of Kenya’s site records for the valley include a tandem out-and-return world record of 257 kilometres and a hang-gliding out-and-return world record of 377 kilometres, along with open distance and triangle records in the hundreds of kilometres. Pilots come from Europe for the conditions, and the valley has hosted both local and international competition.

There is no separate national activity guide for paragliding on this site, so the practical points belong here: flying is arranged through the clubs and operators based on the escarpment around Iten, tandem flights are available to people with no experience, and the season follows the drier months, since thermals collapse and launches close in sustained rain.

Getting to the Kerio Valley

Eldoret is the nearest airport with connections from Nairobi, and Iten on the western rim is a short drive from it. From Iten the road drops into the valley and climbs the far side towards Kabarnet in Baringo County, which is the classic crossing and a spectacular piece of driving in either direction.

From the east the valley is reached through Kabarnet, itself approached from Nakuru by way of the Rift Valley lakes. That makes a loop possible: the lakes, Kabarnet, across the valley, up to Iten, and on to Kakamega Forest or Mount Elgon in the west.

Tarmac reaches both rims and the main crossing. Four-wheel drive earns its keep on the tracks down to the reserves and the river, and on the escarpment in wet weather, when the descents become genuinely slippery.

When to Visit the Kerio Valley

The floor is hot year round and the rim is temperate year round, so the season is decided by rain rather than by temperature. The long rains from mid-March into June and the short rains from October into December make the escarpment roads heavy and interrupt flying. June to early October and January to February are the steadier stretches for driving, walking and paragliding alike.

Whatever the month, the valley floor should be treated as hot country: early starts, plenty of water, and the middle of the day spent out of the sun. Visitors who have only experienced the highland side of the escarpment routinely underestimate it.

Questions Travellers Ask About the Kerio Valley