Maha Pasan Guha 

Burmese term meaning ‘the great cave’ and denoting an artificial cave built in the north of Rangoon, Burma. It was here that the Sixth Buddhist Council was held in 1956, to coincide with the 2,500th anniversary of the Buddha's enlightenment (bodhi).

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)