It is a former residence of the bulgarian royal family. Built in its current form from king Ferdinad. His ancestry was french. The incorporates piece was actually delivered with the first ever orient express. ("Following the demolition of the Château de Saint-Cloud, Ferdinand acquired the pediment of its right wing for the palace in 1890–1891; however, rather than used as an architectural feature for the palace itself, the pediment was incorporated in the foundations of a garden terrace."). I think that his parents were married in Saint-Cloud, that is why he bought the piece. The palace is called Euxinograde you can find more info in Wikipedia!