Towers of a Jain temple in the Fort city of Jaisalmer.Jaisalmer, is an important ancient trading centre because of its strategic location on the camel trade routes. It is often described as the 'golden city'. The havelis, built by merchants of the 19th century, are exquisitely carved from golden-yellow sandstone and are still in a beautiful condition. The fort built by Rawal Jaisal in the 12th century, stands on the 80 metre high Trikuta hill, with beautifully carved Jain temples. Today, walking through the narrow cobbled streets, evidence of the city's rich trading past is everywhere. The ancient fort, the oldest in Rajasthan, and perhaps the oldest still-inhabited citadel in the world, soars 300 meters above a maze of streets, squares, palaces, and clusters of dwellings, all in the local golden yellow sandstone. Atop the Trikuta (triple-peaked) hill, where, as legend has it, a Brahmin hermit related to Jaisal the prophesy that Krishna and Arjuna ruler would one day build a fort, life goes on, almost as it has for centuries. Paradoxically increased consumption (and therefore waste), due to growing tourism and population, put unbearable pressure on the city's aged infrastructure with water being piped in at a daily rate of some 120 litres per head - at least 12 times the amount originally used meant that the old drainage system, _ open gulleys at the sides of streets intended for a time when waste water was minimal was no longer adequate_ water became the enemy.