Located on a vast private park near Brussels, in Belgium, the Groenhoven Estate dates from the 17th century; the property has been called the first "eco-castle" in Europe, with giant solar panels and a recyling system for rainwater. Architects Bateille & Ibens renovated the interiors, seamlessly integrating modern elements with a collection of Old Master paintings. The estate now functions as a venue for conferences, weddings, and other events.