Jethawana Stupa, holds the title of being the largest stupa in the country. Standing at an impressive height of 400 feet (122 meters), it was once the third tallest structure globally. To this day, Jethawanaramaya continues to stand as the tallest brick monument of its kind worldwide.
In the era of King Gothabhaya (253-266 CE), a dispute arose between the monks of Maha Vihara Monastery and the Abhayagiri Monastery over the Vetulya doctrine. King Gotabhaya sided with Maha Vihara and exiled 60 monks who followed the Vetulya doctrine from Abhayagiri Monastery.
One of the banished monks' disciples, Sangamitta Thero, sought revenge against the bikkus of Maha Viharaya. Upon returning to Sri Lanka, he gained the favor of King Gotabhaya (253-266 AC) and was entrusted with the education of the king's two sons, Prince Mahasena and Prince Jetthatissa. Following their father's demise, Prince Jetthatissa, a supporter of the Mahavihara monks, ascended the throne and reigned for a decade (266-276 CE). In 276, Mahasena (276-303) succeeded his brother as king and convinced him that the Mahaviharians lacked discipline, while the monks of Abhayagiri vihara preached the true teachings of the Buddha. He also persuaded the king to prohibit the giving of alms to the Mahaviharians, resulting in their retreat to the hills and Rohana. Sangamittha Thero then convinced the king to demolish the Maha Vihara buildings and utilize the materials to construct a new rival institution within the boundaries of Maha Vihara itself. This new establishment came to be known as Jethawanaramaya (Jethawana Viharaya). Jethawanaramaya Viharaya was erected on the 14th site, which had been blessed by the presence of Buddha in Sri Lanka. Consequently, this location holds the 14th position among the Solosmasthana, the Sixteen Buddhist Sacred Sites sanctified by Buddha, and is also one of the Atamasthana, the eight most sacred holy sites in Anuradhapura. However, this action sparked a devastating civil war, resulting in the death of the monk Sangamitta at the hands of the king's queen. Later, succumbing to public pressure, the king restored the Maha Vihara buildings and ruled for 27 years.
The edifice's perimeter measures approximately 1,200 feet, with a height of 249 feet. It is situated on a platform known as Salapatala Maluwa, paved with square stone slabs spanning about 580 feet from east to west and north to south. Surrounding this maluwa is a sandy compound called Weli Maluwa, with a width of 125 feet.
The platform used to have a half wall around it, while the Weli Maluwa was enclosed by a stone rampart. Jethawanaramaya was constructed by King Mahasena of Anuradhapura (276-303) and was later completed by his son Sirimeghavanna. It is believed that this stupa was built on the site where Mahinda Maha Thero was cremated. Recent excavations at the stupa revealed a one-meter-thick brick wall near a layer of ash and charcoal, believed to be the resting place of the great thero's remains. During the years 1873 AC to 1874 AC, the British mistakenly identified Jethawanaramaya as Abhayagiriya. Therefore, when consulting older documents, this misidentification should be taken into account.
Sir Emerson Tennent's observations on this stupa are as follows: "The sheer mass of masonry in this enormous mound is astounding. With a diameter of 360 feet and a current height of 249 feet (including the pedestal and spire), the contents of the semicircular brick dome and the 720 feet square stone platform, 15 feet high, exceed twenty million cubic feet. Even with modern labor-saving techniques, constructing such a mass would require 500 bricklayers working for six to seven years and cost at least a million pounds.
The materials used could build eight thousand houses, each with a twenty-foot frontage, forming thirty streets half a mile long. They could construct a town the size of Ipswich or Coventry, line a railway tunnel twenty miles long, or build a wall one foot thick and ten feet high stretching from London to Edinburgh.