An oral tradition verified by archaeology
The Mahavamsa, Sri Lanka's ancient chronicle, records an important meeting in the 3rd century BCE. On the full moon day of the month of Poson, King Devanampiya Tissa was hunting deer on this mountain, then known as Missaka Pawwa. He encountered Arahat Mahinda, a Buddhist monk and son of the Mauryan Emperor Ashoka from India. Before sharing his teachings, Mahinda tested the king's intelligence with a series of logical riddles involving mango trees. Satisfied with the king's reasoning, Mahinda delivered a sermon, and the king, along with his retinue, converted to Buddhism.
This account, long held as tradition, finds strong support in the archaeological record. Inscriptions and the remains of monastic structures appear suddenly in this area, dating to the mid-3rd century BCE. Prior to this date, such architecture was absent. The earliest evidence includes dozens of rock shelters, or caves, modified for monastic life. Drip ledges were cut into the rock above the cave entrances to keep rainwater out—a simple but effective architectural feature that appears with no local precedent. Below these ledges, some of the island's earliest inscriptions, written in Brahmi script, record the donation of the caves to the Sangha (the community of monks). King Devanampiya Tissa himself is said to have prepared 68 such caves.
The monastic blueprint
The site rapidly grew into a major monastic complex. The mountain is ascended by a 1,840-step granite stairway. Among the ruins is the Kantaka Chetiya, a stupa with a base circumference of about 130 meters (425 feet). While its dome is now reduced to a height of 12 meters (40 feet), it likely stood over 30 meters tall. Its four vahalkadas, or frontispieces, are some of the best-preserved examples from this early period and feature complex carvings of dwarfs, animals, and floral motifs.
Other important structures include the Ambasthala Dagaba, or Mango Tree Stupa, which tradition holds marks the exact spot of the meeting between the king and Mahinda. The ruins of a large refectory, or dining hall, contain a massive stone trough designed to hold rice, showing the capacity to feed a large population of resident monks. Near the base of the mountain are the remains of one of the world's oldest hospitals, dating back to the 3rd century CE, which includes stone troughs used for medicinal baths. The presence of these specialized buildings, appearing in a concentrated period, provides physical evidence for the organized, communal monasticism described in historical chronicles following Mahinda's arrival.