By Justin Calderon, CNN
Anuradhapura, Sri Lanka (CNN) — Visit the ancient city of Anuradhapura on a full moon day and the past feels anything but distant.
Buddhist pilgrims dressed in white walk barefoot along dusty paths. Saffron-robed monks chant at dawn. Foreign visitors — from Taiwan to Canada — join local worshipers in rituals that have been performed here, largely uninterrupted, for more than 2,000 years.
Set on Sri Lanka’s north-central plains, Anuradhapura was the island’s first great capital. Today, it remains one of the most sacred cities in the Buddhist world, known as the first place to adopt Buddhism outside of India. Scattered across its vast archaeological park are monasteries, reservoirs and stupas that rank among the most ambitious religious monuments ever built.
Towering above them is the immense, bubble-shaped dome of Jetavanaramaya — a structure so large that when it was completed in the early fourth century CE, it ranked as the third-largest man‑made building on Earth, surpassed only by the Great Pyramids of Giza.
Completed around 301 CE using an estimated 93.3 million baked mud bricks, the stupa originally rose to around 122 meters (400 feet), making it one of the tallest structures of the ancient world.
Today, after centuries of collapse, abandonment and restoration, Jetavanaramaya stands at roughly 71 meters (233 feet) — still monumental, but little more than half its original height. Even so, it remains the largest brick structure by volume ever constructed.
So vast is its mass that archaeologists estimate its bricks could build a three-foot-high wall stretching from London to Edinburgh — or from New York City to Pittsburgh.
Yet outside Sri Lanka, Jetavanaramaya is little known. Unlike the pyramids, it was not continuously visible to history. Jungle growth, shifting religious priorities and selective preservation gradually buried both the monument and much of its story, leaving one of the ancient world’s greatest engineering achievements largely forgotten.
Lost — and rediscovered
Jetavanaramaya refers not only to the stupa itself, but to the heart of a vast monastic complex known as Jetavana Vihara, designed to house hundreds of monks. Every structure in the complex was oriented toward the stupa, ensuring that monks stepping outside their residences would face it first — a daily reminder of devotion and cosmological order.
“About 200 monks lived here,” explains Godamune Pannaseeha, a bespectacled monk and senior archaeology officer in Anuradhapura, and one of the foremost contemporary experts on Jetavanaramaya.
“People came to offer robes, books, food — everything — to gain merit,” he says, pointing to the lower terraces of the stupa where offerings were once made, while walking a slow, clockwise circuit around its base. “This was a living religious city.”
From the outset, however, Jetavanaramaya was controversial. It was built on land traditionally associated with the Maha Vihara, the orthodox Theravada Buddhist establishment, reportedly without the consent of its monks. The complex later became associated with the Sagalika sect, which followed Mahayana‑leaning doctrines.
No Mahayana chronicles from ancient Sri Lanka have survived. Today, Sri Lanka remains a predominantly Theravada Buddhist nation. As a result, much of Jetavanaramaya’s history — including the political and doctrinal tensions surrounding its creation — must be reconstructed indirectly, leaving historians with incomplete and sometimes contested versions.
Ancient engineering at an immense scale
The technical challenges involved in building Jetavanaramaya were immense. Unlike Egypt’s stone pyramids, this colossal structure was built almost entirely from mud bricks — a material far more vulnerable to erosion and collapse.
“To replace one stone block, yo