They are unique relics of early commercial architecture. As early as in the 13th century there used to be herring stalls here that also sold salt, candles and torches, as well as some every day items. In the late 15th and 16th centuries the wooden sheds were replaced with narrow, often single - window brick houses with shops downstairs and living quarters on higher floors. The entrances to the stores were protected by arcades, walled up in the 19th century. During the post - war reconstruction the houses were restored to their original form. The arches of the arcades are supported by small sandstone columns; most of them original (house number 11 column bears the date 1535). The southernmost house, dating back to 1538, is known as the City Chancellery or the House of Scribes. Until the 18th century the city scribe lived in it; today it houses the Society of Friends of Poznań. In the arcades Poznań artists sell their paintings, most of them depicting the Old Market Square.