Engaruka
Engaruka is an abandoned system of ruins in the Great Rift Valley of northern Tanzania (2°58′58.80″S 35°57′0.00″E / 2.9830000°S 35.9500000°ECoordinates: 2°58′58.80″S 35°57′0.00″E / 2.9830000°S 35.9500000°E). Situated in the Arusha province, it is famed for its irrigation and cultivation structures. It is considered one of the most important archaeological sites in the Great Lakes region.
Sometime in the 15th century, an iron age farming community with a large continuous village area on the footslopes of the Rift Valley escarpment, housing several thousand people developed an intricate irrigation and cultivation system, involving a stone-block canal channelling water from the "Crater Highlands" rift escarpment to stonelined cultivation terraces (Stump, Daryl 2006, Laulumaa, Vesa 2006). Measures were taken to prevent soil erosion and the fertility of the plots was increased by using the manure of stall fed cattle. For an unknown reason Engaruka was abandoned at latest in the mid-18th century. The site still poses many questions, including the identity of the founders, how they developed such an ingenious farming system, and why they left (Stump, Daryl 2003).
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