Kathmandu Durbar Square, also called Basantapur, is the historic royal plaza at the centre of the old city and one of three UNESCO World Heritage Durbar Squares in the Kathmandu Valley (the other two being in Patan and Bhaktapur). It is a dense concentration of medieval temples, palaces, courtyards, and statues accumulated over centuries of Malla rule — the effect on first arrival is overwhelming.
The main sights within the square include the Hanuman Dhoka palace complex, the Kumari Ghar (house of the living goddess), the Taleju Temple, the Kasthamandap pavilion, and the Jagannath Temple with its famous erotic carvings. Entry to the square costs a fee for foreigners; the ticket is sold at the square entrance and also covers several other monuments. Budget at least three hours — more if you want to sit and absorb the constant activity of pigeons, sadhus, schoolchildren, and vendors.