Jacob van Thienen

Jacob 'van Thienen' was a Flemish architect of the early 15th century. He is believed to have designed Brussels' Town Hall, around 1402. The Brabantine Gothic building, which stands in the city's Grand-Place/Grote Markt, is widely regarded as a masterpiece of medieval European secular architecture. The building's distinctive tower was, however, the work of a different architect, Jan van Ruysbroeck.
Van Thienen may also have built the southern aisle of the Cathedral of St. Michael and St. Gudula in Brussels, around 1400.