The square's southern side is graced by a distinguished Town Hall dating from the beginning of the 15th century. Today it is restored to the way it looked when it was completed in 1404. The main facade overlooking the square is supported by an arcade that was previously used for buying and selling. The Renaissance-era spire is from the 17th century. At the tip stands Old Thomas, a statue of a medieval town sentry. The original, from 1530, is inside the building.
The city government or Rat met in the hall on the main floor. It is flanked by a gallery where citizens sat. As in many port and trading towns, the lowest floor was a trading hall and wine cellar. The tastefully-restored rooms feature paintings from the Blackheads collection, the Biblical paintings of Tallinn painter Johann Aken, the woodwork of Elert Thiele and Joachim Armbrust, frescoes from the 17th centuries and aldermen's benches dating from the 14th century and decorated with wood reliefs of Biblical scenes. Also of interest: a plaque above the entrance to the hall admonishing town elders to be just, and a large Tallinn coat of arms with the three leopards above the stairwell.