Diocletian's Palace, Split (must see)

Call it a palace if you like, but Diocletian’s masterpiece is really part imperial retirement villa, part military fortress, and part living city. Built at the end of the third century AD for the Roman emperor who gave up power in favor of peace (and yes, cabbages), it’s a place where stone walls once sheltered soldiers, emperors, monks—and today, generations of Split’s residents.

Perched on a peninsula near Salona—then Dalmatia’s Roman capital and Diocletian’s birthplace—the palace originally served as a seaside sanctuary for the emperor’s final years. When he died in 312, the complex remained under Roman control and occasionally offered refuge to members of the imperial family who needed to lay low.

In the 7th century, when Slavic and Avar invaders destroyed Salona, survivors escaped behind these formidable walls, founding a new settlement right inside the palace. And here’s the surprise—they never left. Today, Split’s Old Town literally lives within those ancient foundations: temples transformed into churches, courtyards became vibrant squares, and homes sprang up between columns.

Later transformations added layers of history. The emperor’s mausoleum was converted into what is now recognized as the world’s oldest Catholic cathedral still in use in its original structure—the Cathedral of Domnius. In the 18th century, Scottish architect Robert Adam studied the palace ruins and helped inspire the elegance of Neoclassical architecture across Europe.

The palace’s layout originally formed an irregular rectangle, once fortified by 16 defensive towers. Its southern façade opened directly to the sea, with ships docking at what is still known as the Sea Gate. Three other gates connected the city walls to external routes: the Golden Gate to the north, leading toward Salona; the Silver Gate to the east, facing Stobreč; and the Iron Gate on the west, reserved for military access.

Indeed, there are few places like this, where centuries layer so vividly in stone—Roman ambition, medieval resilience, and Venetian finesse all mingle beneath your footsteps...