Windmills brought a new feature to the cityscape in the eighteenth century. According to the tax accounts for the year 1765 there were already five windmills in the city.
      The windmill in Kaivopuisto was the last of the city's many windmills to be built. Building windmills was prohibited in 1825, but despite that the mirror factory owner Strömberg had an unauthorised windmill built in Kaivopuisto in 1832. The lower part of the mill contained the miller's dwelling. The mill was torn down in the beginning of the 1900's but its memory lives on in the name of Myllytie ( 'Mill Street'). Millstones were transferred in due course to the yard of Hakasalmi Villa, which had been converted into a museum. There are also millstones that were found in the Katajanokka canal and millstones brought from the Tali estate.