The Valley is the cultural, political and commercial centre of Nepal and encompasses three cities: Kathmandu the capital; Patan, which has been enveloped by the growing Kathmandu outskirts; and the medieval city of Bhaktapur. For the unprepared visitor, the capital city of Kathmandu can trigger a sensory overload. It is a heaving city of both intriguing and unpleasant smells, incessant noise and pollution, and sights that etch themselves on the memory.