The Adam Brothers’ Adelphi development, begun in 1768, was the most ambitious and controversial building project Georgian London had ever seen. Its site, just south of the Strand, one of London’s main thoroughfares, sloped steeply down to the River Thames. In its planning and engineering the Adelphi showed the Adams at their most ingenious, with streets of well-decorated neoclassical houses raised up above riverside warehousing so as to match the ground level of the Strand. This paper considers the debt that Robert Adam owed in his Adelphi designs to his knowledge and experience of the great city palace of the Emperor Diocletian on the Adriatic at Spalato (always referred to by Adam himself as ‘Spalatro’). Even before his important visit to record the remains there in 1757 he had been experimenting with extravagant palace designs and capricci in Rome – hence the extensive imperial site appealed to an existing predilection for buildings of this type. The similarities between the two complexes are fundamental: a Roman palace of many streets and buildings, for storage, servants and soldiers as well as the royal family, built on a vaulted basement, with a long waterfront façade of curved arches; and the Adelphi, fronting the Thames, its streets of genteel terraced houses for different social classes raised up on arched warehouses. The Adelphi is the classic example of Robert Adam’s ability to take the essential qualities of antique Roman remains and transform them to suit the requirements of eighteenth-century metropolitan society
