This building dates from pre famine times. It acted as a market house for the town and surrounding areas and as a meeting place of the Town Commissioners. It was also the birthplace of the Callan Tenants Association founded in 1849 at the height of the evictions and which one year later was a countrywide organisation.
Evidence of its early use is seen in its three spacious doorways and a weighing scales which was used on market days so that people could weigh their produce before selling. This scales was in use up to 1940. Its upper floor was used as a reading room by the Town Commissioners. The 'Mace' or symbol of office of the old Callan Corporation is dated 1632.