On his excursions and hikes in the environs of Rome Hackert compiled a collection of drawings and sketches of famous architecture and antique artworks, characteristic landscapes, and typical tree shapes that he deployed repeatedly in his paintings. Here it is the ensemble of the round mausoleum and the antique bridge over the Aniene southwest of Tivoli. The same group can be found earlier in the middle distance of the large ideal landscape of 1774.