Lake Naivasha.

Lake Naivasha is a freshwater jewel of the Great Rift Valley, its papyrus-lined shores and open waters home to one of Kenya's densest hippo populations and prolific birdlife, from fish eagles to pelicans. Boat safaris glide close to grazing hippos and basking crocodiles, while a crossing to Crescent Island allows rare walking safaris among giraffe, zebra, and waterbuck with no predators in sight. Towering above the lake, the dormant volcano Mount Longonot offers a rewarding day hike up to its crater rim, just an hour from Nairobi.