Since April 2006, the Königsbau-Passagen, a 45,000 square meter retail and commercial building, has been attached to the rear of the Königsbau.
The Königsbau was built between 1856 and 1860 by order of King Wilhelm I in late classicist style as a business, concert and ball house.
After Knapp retired from work in 1857, partly for health reasons, Leins completed the construction.
The monumental building was intended to form a counterpoint to the New Palace and is characterized by a colonnade consisting of 34 columns, 135 meters long.
During World War II, the Königsbau was severely damaged, and in 1958 and 1959 it was rebuilt at a cost of the equivalent of €4 million.