Originally built for the Danish royal family as a replacement for the palace that burnt down (but as mentioned yesterday, it turned out that they preferred the Amelienborg Palace), Christiansborg Palace is today the seat of the Danish Parliament, the Danish Prime Minister's Office and the Danish Supreme Court. Also, several parts of the palace are used by the monarchy, including the Royal Reception Rooms, the Palace Chapel and the Royal Stables.
As a result, the palace is the seat of Denmark's three supreme powers: the executive power, the legislative power, and the judicial power; it is the only building in the world that houses all three of a country's branches of government.
Here's an interesting fact - the Danish King or Queen is not crowned; rather, they are pronounced - on the death of the reigning monarch, the Prime Minister appears on the central balcony above and announces 3 times "King/Queen X is dead, long live King/Queen Y" - and it's done, Denmark has a new head of state. You have to love the simplicity of it - something about the Danish love of practicality perhaps!
The ruins are really well detailed, with descriptions of the building of the original castle (Absolom's Castle, after the Crusader-Bishop who built his castle here) to the current building. The stables are filled to the brim with about 20 carriages of various times and styles. Upstairs, the Royal Reception Rooms are, as you would imagine, quite stunning; from where I will share photos:
It is most noted for its 7.5-turn 209 metre long helical corridor (no steps until the very top - a nice change) leading to the top, and for the expansive views it affords over Copenhagen from a height of around 35 metres above street level:
I have to admit that I liked the Modern Art section as little as I expected that I would - but I did try; perhaps I am an uneducated heathen, but I just don't get the point of most of it.
Anyway, as photos were allowed (no flash, of course), here is a selection of some of the ones that I did like: