Where to start with all the reasons to visit Tanzania? If the safari bug has bitten you, then ticking off the Serengeti, Ngorongoro Crater and Selous (or Nyerere National Park) is a no-brainer. This is Big Sky country and the amazing wildlife experience brought to you by Swahili guides is nothing short of intoxicating. The Serengeti hosts the bulk of the Wildebeest Migration as they return from Kenya in about November and stay in Tanzania until midyear, rutting, mating, giving birth and crossing rivers filled with hippos and crocodiles in the space of a few months. The timing of river crossings is totally unpredictable as the blue gnu might mass on the riverbank and swim across immediately, or hang around for days, keeping safari goers on tenterhooks.