Many travellers’ first proper view of the Rift Valley is from the souvenir-draped B3 Escarpment Road, originally built by Italian prisoners-of-war during World War II. This flirts with the precipice before dropping steeply down to the Rift through candelabra euphorbia and spikey agave. The little chapel at the bottom, also Italian-built, and often used as a picnic site, seems fitting in this Mediterranean scene.
The alternative route, the A104 Uplands Road, goes slightly farther north and joins the B3 at Naivasha. Out of northwest Nairobi, it crosses a broad, bleak plateau, where roadside traders sell rhubarb, plums, carrots and potatoes, and where, in the wet season, you can find yourself driving over a thick carpet of hailstones between gloomy conifer plantations. All this contrasts dramatically with the dusty plains of the Rift Valley. When you start descending, get out your binoculars and you can pick out herds of gazelle, Maasai with their cattle and, bizarrely, a satellite-tracking station.
For years the Uplands Road was the better of the two routes, but they’re currently both in reasonable shape, though if you’re climbing the steep and winding B3 back towards Nairobi on a busy day, it can be slow going in the fumes and traffic. On the escarpment section, roadside souvenir stands sell crafts and small sheepskins (the latter often excellent value, though they’re not always very well cured, so don’t last long).