The baroque and rococo Schloss Charlottenburg in Berlin dates back to the late 1600s, and was the favourite home of Fredrick, King of Prussia - although it was actually commissioned and built by his less well-known father, Frederick the First.
Now visitors will once again be able to see the freshly-renovated "New Wing" (actually buit by Fredrick the Great between 1740-42), which has spent the past two years under tarpaulins as a 4.5 million euro refit saw the roof and facades fully-renovated.
The grand re-opening will be on Boxing Day, in the hope of luring Berliners who have over-indulged during the Christmas period to also walk through the splendid formal gardens and grounds.
The major draw is the magnificent "White Salon", in the New, or East wing, as well as Fredrick the Great's collection of 18th century French paintings.
The entire castle is undergoing a €14.3 million renovation, paid for by both the Berlin and Brandenburg state governments, which will only finally be finished in 2017.
The royal Hohenzollern family were finally overthrown in the German revolution after the First World War, and the palace itself suffered major bomb damage in the Second World War.
The current renovations are aimed at lengthening the life of the palace since the last renovations took place in the 1950s and 1960s
Despite Berlin's staunchly leftwing politics, the palace is a major international tourist draw and major-money spinner for the city.