The Old Town Hall is located in the middle of the Old Rauma by the market square and it is one of the most recognizable landmarks in Rauma. The building is also a de facto icon of the Old Rauma together with the Church of the Holy Cross. The building unites the baroque style and the common medieval european town hall layout with two storeys and a clock tower.
The final design was made at the end of the 18th century by Christian Schröder, the town architect of Turku. The tower was designed and built by Anders Wahlberg, a building master from Turku. The unusually steep roof required also craftsmen skilled in church constructions, such as Job Höckert, the clerk of Lappi parish. The building was completed in 1776 and it hosted the town council and archives, town jail and stores.
Since the beginning of the 20th century the building has been a city museum. Nowadays there are historical items related to the city history, seafaring and lace making.