One thing I'm reading is a book by Rick Ridgeway: The Shadow of Kilimanjaro: On Foot Across East Africa is a story of his trek over the mountain and to the coast - a 500 Km walk with guides and guards with rifles. Included are tales of other treks where people got eaten by hippos, hyenas, and lions or in some cases partially eaten and lived to tell the tale. We'll be nearby some of his path (NOT on foot) such as in Amboseli National park which is right near the base of Mt. Kilimanjaro.
I have another book from the library about culture and history: Nine Faces of Kenya by Elspeth Huxley (including such things as finding homo erectus skeletons and prior such things. For some reason she doesn't describe contra dance as one of the things done in Kenya.
At some time in the future we will need to get some immunizations and take anti-malaria medicine before, during, and after the trip.
Of course, I had to look up the railroad situation. Kenya Railways has trains from Nairobi to Mombasa and Nairobi to Kisumu. Both are overnight trips. First class cabins with 2 bunks in a cabin only cost about $60 a person. I don't think we'll even seriously consider doing it, although it is intriguing to think of seeing the Indian Ocean. Also I read that there have been derailments and worse because of deteriorating infrastructure, but there seems to be some improvement on that front these days. The warning is to take mosquito repellant, bottled water, and toilet paper. They do have a dining car. They certainly have a very nice logo.