The beautiful hill-country of Southwest Uganda and Rwanda supports one of the highest human population densities in Africa. Consequently, every square inch of this fertile volcanic land is tilled and crudely terraced on steep hill slopes to prevent erosion. Blessed with good rainfall, almost every conceivable crop is grown.The evidence of recent (in geological terms) volcanic activity is everywhere. The two most westerly volcanoes of the Virunga chain are still active.