Mariemont is named after Mary of Hungary, for whom J de Broeucq built the first castle in 1546. It was destroyed by Henri II, then immediately rebuilt and extended by W Coberger. In the park, there are ruins of another castle built by Charles of Lorraine in the 18C and burnt down in 1794. The Warocqué dynasty of industrialists transformed the estate in the 19C, but a fire razed the castle in 1960. Since 1975, a Museum of Modern Art has stood on the site.