The four major Buddhist and Hindu temples in Kathmandu valley, UNESCO World Heritage site. 1. Swayambhunath is an ancient (about 5th century) Buddhist temple complex on a hill in Kathmandu . Also known as Monkey Temple. 2. Boudhanath stupa is one of the largest Buddhist stupas in the world, the holiest Tibetan Buddhist temple outside Tibet. 3. Pashupatinath is an ancient Hindu temple in the Kathmandu valley (5th century), considered the most sacred Shiva temple. 4. Changu Narayan is a Hindu temple, possibly the oldest temple of Nepal (4th century).