The Kathmandu Valley holds three royal cities — Kathmandu, Patan and Bhaktapur — each with its own Durbar Square of palaces and pagoda temples. Together with the great stupas of Swayambhunath and Boudhanath and the Hindu temples of Pashupatinath and Changu Narayan, they form a single UNESCO World Heritage site.
What makes the valley special is that its heritage is still in daily use. Offerings of rice and marigolds appear at street-corner shrines every morning, pilgrims circle Boudhanath at dusk, and festivals pull chariots through the same squares they have for centuries.
Give yourself time to wander: the lanes between Kathmandu's Durbar Square and Asan market, the courtyards of Patan, and the potters' squares of Bhaktapur reward slow exploring more than a checklist. Entry tickets are charged for foreign visitors at the main squares, and the money goes to their upkeep.
