The Kayserburg is a palatial building at the Hellbrunner Allee, the long lane that connects the leisure palace of Hellbrunn with the city centre of Salzburg. It is one of several chateaux on this route; other significant ones include Freisaal, Lasserhof, Frohnburg, Emslieb and Emsburg. The name does nor refer to the German word "Kaiser" ("Emperor"), but to a man whose surname was Kayser. The Kayserburg can be found right next to the Lasserhof and its administrative building; it is therefore often mistaken as being associated with the Lasserhof. This is not not the case, the Kayserburg is a separate property and was developed as such.
The Kayserburg is a relatively plain building with three floors. On the western fašade you can spot a marble plate with the coat of arms of a former owner of the property, a certain Mr. Imhof. The first owner was presumably the person who built the property, a member of the guard of Prince Archbishop Paris Lodron: Hans Kayser. The palace of Hellbrunn was completed only a few years earlier and the high-ranking official was rewarded with a nice piece of land close to his master.
After the death of Hans Kayser, his brother-in-law Philipp Vermeulen inherited the property. This was only the first of a long series of different owners, most of them noble or at least very wealthy: Ferdinand Count Martiniz (1689), Abraham Zillner von Zillerberg (1695), Family Thun und Hohenstein (1706), Knights von Rehlingen (1830), Counts von Kuenburg (1854), Sir Max von Imhof (he of the coat of arms; 1904), Counts of Ledochowski (1929). The Kayserburg is still private property and not open to the general public. The area is very rewarding for extended walks, though, and among the nicest of Salzburg.
Hidden Treasures of Salzburg
The Kayserburg on the German Wikipedia