His churches, palaces, grand houses, interiors, city gates and theatres in Silesia (now Poland), Berlin, Potsdam and elsewhere belong to the earliest examples of Neoclassical architecture in Germany.
In the same year, he received an appointment as building inspector for the Count of Hatzfeld, whose war-ravaged palace Langhans rebuilt to his own design between 1766 and 1774.
Another influential late classicist architect was David Gilly, an architectural advisor in the Royal Building Department, who was younger than Langhans and overtook him in terms of modernity, but did not outlive him, leaving a considerably smaller life's work.
The fulfillment of this dream was not granted only to Goethe and Schinkel, but Langhans, too, was able to afford a trip in 1768 and 1769 thanks to the support of the Count of Hatzfeld.
When he was later assigned to be the head of the Breslau war and dominion chamber, he visited England, Holland, Belgium, and France on behalf of and at the expense of the king.