Located about 11 km (6.8 mi) from the center and northeastern outskirts of Kathmandu, Boudhanath Stupa’s massive mandala makes it one of the largest spherical stupas in Nepal. Boudhanath Stupa is one of the most attractive stupas and has been a popular tourist destination in Kathmandu Valley. The stupa was enlisted as a UNESCO World Heritage site during the year 1979.
The Stupa is an ancient trade route from Tibet which enters the Kathmandu Valley by the village of Sankhu in the northeast corner, passes by Boudha Stupa to the ancient and smaller stupa of Chā-bahī named Charumati Stupa (often called "Little Boudhanath"). The stupa has its own mythology for why and how it was built in Newar Buddhist mythology.
According to the history of Nepal, the palace of King Vikramaditya (Licchavi King) once stood where the Narayanhity Palace currently stands. King Vikramaditya instructed that a Dhunge Dhara should be built in the southern part of the palace courtyard. But there was no sign of water from the Dhunge Dhara, for which the king consulted Astrologers. Astrologers suggested that a Human sacrifice with a male candidate having Battis-Lakshanas, or thirty-two perfections should be performed. Only the king himself and his two princes were suitable candidates. So, the king decided to sacrifice himself and ordered one of his sons to sacrifice him so that sign of water could be seen at the Dhunge Dhara. According to local mythology, during the time of sacrifice, the head flew off to a place nearby Sankhu Bajrayogini Temple. The prince then with a regretful heart flew a hen from the top of Bajrayogini and decided to construct a Stupa where the hen landed. The hen landed in the place where Boudhanath Stupa is currently standing.