Northern Tanzania is a land of extremes—from the snow atop Kilimanjaro, Africa’s highest mountain, to the caustic, boiling waters of Lake Natron, and from the dramatic landscapes of the Great Rift Valley to the molten lava of Ol Doinyo Lengai, East Africa’s only active volcano. Here, you’ll find breeding grounds for more than a million flamingos, as well as the wild, wide, uncultivated plains where the Maasai tribe graze their cattle and sheep…