our reporter joaim egger travelled to peru. every year, millions of tourists visit cusco, latin america's oldest settlement, before making a pilgrimage to the world-famous inca site of machu picchu. and that's a huge challenge for cusco's water utility -- even though it has a tradition spanning centuries. from the source, the water flflows through h channels intoe terraced gardedens of tipo buil600 0 yearago, i it'an idyllic placace. 300 people once lived here, explains a hydraulic engineer who's worked here for decades. the ruin is situated 3,500 meters above sea level and is considered a masterpiece of water management. >> tipon was a huge ecological experiment, where the pre-hispanic people made use of nature and especially water. it was used for rituals and ceremonies and also for agriculture. specific hydraulic systems were developed for these purposes -- for example, the channels, the subterranean cisterns, and the aquaducts. >> the incas succeedededn channelling the water ov a a course o of several hundred mets down the