Prince Frederik, Princess Mary and their children are at Grasten Sabtu, 15 Juli 2017 Celebrity, Fashion, Food, Gossip, Lifestyle, News, Style, Travel, World Crown Princess Mary and Prince Frederik of Denmark with their children Prince Christian, Princess Isabella and Prince Vincent were spotted biking near the Grasten Palace yesterday. Gråsten Palace is one of the summer residences of the royal family. Tweet Subscribe to receive free email updates: