In an otherwise unassuming park in Lede, Belgium, there are the crumbling ruins of a once-stately castle. The Castle of Mesen has stood here since the 1600s, and was initially a home for nobility. Later on, it was converted into an industrial site, a sugar refinery, a gin distillery and a tobacco factory. In 1897, the property was bought by a religious order who added a neo-Gothic chapel and turned the space into a girls' boarding school. It was used exclusively by aristocratic families who had lost their historic money. The castle through the ages, from the 19th century to...