Today is Poson full moon poya day, the day that commemorates the introduction of Buddhism to Sri Lanka by Arahat Maha Mahinda thera.
Poson, held on the full moon day of June, commemorates the occasion over 2,000 years ago when Arahat Mahinda, son of Emperor Asoka of India, converted King Devanampiyatissa to Buddhism.
The main centre of celebration is Mihintale, the ancient monastic complex where the mission headed by the Arahant Mahinda included Itthiya, Utthiya, Sambala and Bhaddasala Theras perched the first sermon to the ruler King Devanampiyatisa, at Anuradhapura, thereby setting in motion a series of events that eventually made Sri Lanka the home of Theravada Buddhism.
The two rituals of pilgrimage and the observance of the Eight Precepts are combined here.
Processions commemorative of the event, referred to as Mihindu Peraheras, are held in various parts of the country.