When the Scottish architect Robert Adam stepped into the ruins of Diocletian’s Palace in Split in 1757, he could not have imagined that this encounter would reshape London’s architectural landscape forever. The towering vaults, waterfront arcades, and sophisticated urban planning of the 1,700-year-old Roman palace captivated him so completely that eleven years later, he embarked on his most ambitious project: recreating this ancient Dalmatian grandeur along the banks of the River Thames.​
The result was the Adelphi Buildings, London’s first neoclassical structure and one of the most audacious architectural ventures Georgian London had ever witnessed. This remarkable project connected two ancient cities separated by centuries and thousands of miles, proving that great architecture transcends both time and geography.​
The Journey from Split to Scottish Genius
Robert Adam arrived in Split expecting to find a simple Roman villa. Instead, he discovered an extraordinary late antique palace that had transformed into a living, breathing medieval city. The palace’s unique character—residential streets built atop massive vaulted substructures, all cascading down toward the Adriatic waterfront—left an indelible impression on the young architect’s imagination.​
Adam spent weeks meticulously surveying and drawing every detail of Diocletian’s Palace. He measured the Peristyle’s columns, studied the basement vaults where Roman soldiers once stored provisions, and traced the long waterfront facade with its distinctive curved arches. These detailed observations would eventually be published in 1764 as “Ruins of the Palace of the Emperor Diocletian at Spalatro in Dalmatia,” one of the most beautifully illustrated architectural books of the eighteenth century.​
What fascinated Adam most was how the palace combined monumental architecture with practical urban living. Split’s residents had adapted the ancient Roman structure into homes, shops, and streets, creating a vibrant mixed-use environment. This concept of a palace functioning as a self-contained city would become the cornerstone of his Adelphi vision.
The Adelphi: Split Reimagined on the Thames
Between 1768 and 1772, the Adam brothers—Robert, John, James, and William—transformed an unfashionable stretch of London’s waterfront called Durham Yard into the magnificent Adelphi Buildings. The name “Adelphi” comes from the Greek word adelphoi meaning “brothers,” a tribute to their collaborative family enterprise.​
The parallels between Diocletian’s Palace and the Adelphi were striking and intentional. Both sites sloped steeply toward the water, requiring extensive engineering to create level ground through massive vaulted substructures. Just as Diocletian’s Palace featured storage spaces and military quarters in its basement supporting grand imperial apartments above, the Adelphi raised elegant Georgian townhouses on top of cavernous riverside warehouses and wharves.​
The architectural similarities extended to the waterfront design. Adam replicated the continuous facade of Split’s seafront, flanked by projecting towers at either end, creating a commanding presence when viewed from the River Thames. The central Royal Terrace (later renamed Adelphi Terrace) housed the finest residences, echoing the hierarchical arrangement of Diocletian’s Palace.​
Robert Adam also embraced the mixed-use urban concept he had witnessed in Split. The Adelphi became a self-contained neighborhood featuring townhouses of various sizes for different social classes, alongside coffee houses, shops, a tavern, hotel, Coutts’ bank, and a purpose-designed headquarters for the Royal Society of Arts on John Adam Street. This diverse environment mirrored how Split’s residents had transformed an ancient palace into a bustling modern city.
Where the Adelphi Stood and What Remains Today
The Adelphi occupied prime London real estate between the Strand—one of London’s main thoroughfares—and the River Thames, in what is now the Westminster district. The development comprised several interconnected streets, including Adelphi Terrace, Robert Street, John Adam Street, and Adam Street, most named after the architect brothers themselves.​
Tragically, most of Adam’s original Adelphi Buildings were demolished in 1936, despite significant public outcry and preservation efforts. The destruction of this neoclassical masterpiece is now considered a pivotal moment in Britain’s nascent architectural preservation movement. Many regarded the demolition as one of London’s great architectural losses.​
The original buildings were replaced between 1936 and 1938 with an imposing Art Deco structure designed by the architectural firm Collcutt & Hamp. This monumental Portland stone building, which controversially retained the name “Adelphi,” still stands today and is itself now a Grade II listed building, valued for its metropolitan Art Deco architecture.​
However, precious fragments of Robert Adam’s original vision survive. The Royal Society of Arts building at 8 John Adam Street remains beautifully intact, featuring original Adam interiors, magnificent plasterwork, James Barry’s stunning painted ceiling sequence, and extensive basement vaults that once formed part of the original warehouse system. Several houses on Robert Street, Adam Street, and John Adam Street also endure, offering glimpses of Adam’s elegant Georgian proportions and distinctive decorative style.​
Visitors to London today can still walk these historic streets and imagine how Diocletian’s Palace inspired this remarkable architectural transplantation. The surviving buildings testify to Robert Adam’s genius in translating ancient Roman monumentality into Georgian sophistication.
Understanding the Connection Between Two Ancient Cities
The architectural dialogue between Split and London reveals how classical inspiration flows across borders and centuries. Robert Adam’s Adelphi demonstrates that studying historic monuments is not about simple imitation but about understanding underlying principles—how buildings relate to water, how structures can serve multiple purposes, how architecture can create urban community.​
The “Adam Style” that emerged from Robert Adam’s studies in Split became one of the most influential architectural movements of the eighteenth century, shaping buildings throughout Britain, Europe, and America. His ability to extract essential qualities from Diocletian’s Palace and reimagine them for Georgian London exemplifies the transformative power of architectural inspiration.​
For British travelers who have admired the Georgian elegance of buildings in Edinburgh, London, or Bath, discovering that these designs originated from a Roman palace in Split adds fascinating depth to both destinations. Walking through Diocletian’s Palace today offers the unique opportunity to see the ancient source of Britain’s beloved neoclassical architecture.​
Experience the Architectural Legacy in Split
Standing within Diocletian’s Palace, you can trace the same arches, vaults, and proportions that captivated Robert Adam nearly 270 years ago. The palace remains remarkably unchanged since his 1757 visit—the Peristyle still showcases those distinctive capitals he sketched, the basement corridors retain their mysterious grandeur, and the urban fabric continues to blend ancient monumentality with contemporary life.​
Understanding this architectural connection enriches your experience of Split immeasurably. You are not simply viewing Roman ruins; you are witnessing the birthplace of a design revolution that shaped the buildings defining British cities.​
Ready to explore where British architectural heritage began? Join a guided walking tour through Diocletian’s Palace and discover the precise spaces that inspired London’s Adelphi Buildings and the broader Adam Style. See the waterfront arcades, explore the atmospheric basement vaults, and understand how this ancient palace became a template for Georgian grandeur. Walk the same streets Robert Adam walked, and experience the architectural inspiration that crossed continents.
Book your expert-led walking tour of Split and uncover the fascinating connections between two of Europe’s most historic cities. Your journey through neoclassical architecture begins here, in the heart of Dalmatia.
