At NBO, stay airside—security and traffic delays make exiting risky for short layovers.
A 3-6 hour layover in Nairobi is possible but requires careful traffic planning. Jomo Kenyatta Airport is 15km from the city, but Nairobi traffic can be extreme during rush hours (7-9am, 5-7pm). If your layover avoids these windows, a taxi to Westgate mall or the city center takes 20-30 minutes. Grab Kenyan chai and nyama choma, then return. Budget 45 minutes each way as a safe estimate.
Six to ten hours in Nairobi is ideal for the Giraffe Centre and Karen Blixen Museum circuit. The Giraffe Centre (20 min from airport) lets you feed endangered Rothschild giraffes from a raised platform at eye level - one of the best animal experiences in Africa ($15 entry, open 9am-5pm). Karen Blixen Museum (5 min from Giraffe Centre) is the preserved farmhouse from Out of Africa, set in beautiful grounds ($12 entry). Return to the airport 90 minutes before your flight. Eat at any nearby Karen Blixen-area restaurant for nyama choma and ugali.
With 10+ hours, add Nairobi National Park to your itinerary. This is the only national park in the world with a major city skyline as backdrop - lions, rhinos, giraffes, and buffalo roam with the Nairobi CBD visible behind them. Park entrance is $60 for non-residents; shared safari vehicles operate from the main gate (15 min from airport). Morning game drives (6-9am) offer the best wildlife sightings. The David Sheldrick Wildlife Trust elephant orphanage near the park entrance has an exceptional daily visiting hour (11am, $8 donation). Karura Forest within the city boundary offers walking and cycling trails through indigenous forest - peaceful and genuinely wild.