The Udzungwa Mountains are almost unearthly. An enchanted forest of leafy glades, freckled with sunshine, where fungus, lichen, moss and ferns ingratiate themselves into every damp crevice, it is at once both vivid detail and larger than life. A new variety of African violet was discovered in the shelter of a 30m high tree. It is a hothouse, nurturing species found nowhere else on earth, a secret bank account of precious genetic stock. Of its six types of primate, two Sanje-crested Mangabey, not discovered until 1979. Four previously unknown birds, including the Rufous like francolin, make this Tanzania’s richest forest bird habitat and among the three most important bird conservation areas on the continent. One of East African’s great forests, this undisturbed habitat undoubtedly has new treasures yet to reveal. A link in the chain of Africa’s eastern arc mountains, Udzungwa is made for hiking and climbing on trails through the rainforest and along the escarpments. The plateau is a natural tower top, with views of sugar plantations against a patchwork of grassland and mountain forest extending over 100 km. but the centerpiece is the Sanje River, which reinvents itself into a spectacular waterfall, plunging 170m through the forest to land in a mist in the valley below. Visit Udzungwa year around, but be prepared for rain any time.