This is the third Christiansborg built on the site. The current palace houses the Danish Parliament, the Royal Reception Rooms, the Prime Minister's Office as well as the Supreme Court. In an attached building is the Royal Stables and Carriages. After donning plastic booties to cover your shoes, you are free to wander the Royal Reception rooms (keeping to the roped-off areas). The Throne Room, The Great Hall, the marvelous tapestries, The Dining Hall, etc are open to view (and photograph). The ruins of Absalon's Castle and Copenhagen Castle were closed when we visited, but I believe that they are also worth visiting.
The Royal Stables were open as the horses had not yet been returned from their summer holiday. The carriages were quite interesting as was the stables themselves.
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