The Metcalfe Hall, named after Lord Metcalfe, who officiated as Governor General of India from March 1835 to March 1836. The architecture shows clear Greek influences. It was originally conceptualised as library. The annex building of the Asiatic Society is on the ground floor. The Archaeological Survey Of India (ASI) has a small museum on the upper floor.
Photo credit: http://commons.wikimedia.org/wiki/File:Metcalfe_Hall.JPG