Laxenburg castles are imperial palaces and castles outside Vienna, in the town of Laxenburg owned in equal parts by Vienna and Lower Austria. The castles became a Habsburg possession in 1333 and formerly served as a summer retreat, along with Schönbrunn palace, for the imperial Habsburg dynasty. Blauer Hof Palace was the birthplace of some members of the royal family, including Crown Prince Rudolf. Another castle nearby is named Franzensburg castle.
Today the castles are used for events, conferences, and concerts. The castles also acts as a museum in preserving the various paintings and furnishings contained within.
Wikipedia https://en.wikipedia.org/wiki/Laxenburg_castles
Coordinates 48°4'4.272" N 16°21'29.575" E