The Jetavanaramaya is a stupa, located in the ruins of Jetavana Monastery in the sacred world heritage city of Anuradhapura, Sri Lanka. With two Egyptian pyramids, standing at a height of 400 feet (122 m), it was one of the tallest monuments in the ancient world. It is still the tallest & largest structure made entirely of brick anywhere on earth.
This amazing stupa was built in the 3rd century AD by King Mahasena. The monastry once housed 10,000 Buddhist monks. Until 1909 the structure was covered with jungle shrub.