The current building town hall has two faces. A huge fire during the winter of 1929 destroyed all of town hall except the facade on the side of the Breestraat. This is the only remaining part of the medival town hall, build in 1597, only 23 years after the Spaniards were defeated who layed a siege around Leiden in 1573/1574. The current building (1929, C. Blaauw) is located on Town hall square which was also a result of the fire as it burned down several adjacent houses. The tower is a lookalike of the burned down tower and is 53 m high.
Info 1: http://leiden-info.com/bezienswaardigheden/stadhuisleiden/ (Dutch)
Info 2: http://www.architectenweb.nl/aweb/archipedia/archipedia.asp?ID=332 (Dutch)