After the Great Siege, a colonnaded Georgian guardhouse was built on the southern side of John Mackintosh Square. It was the Main Guard, from where all the sentries in Gibraltar were posted each evening. Some years later it hosted the Fire Brigade. After the move of the brigade to the new fire station at Victoria Battery in 1938, it became the Rates Office, later the Arrears Section and Transport department. Today the old guardhouse houses the Gibraltar Heritage Trust and a Gibraltar Tourist Board information counter.