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.