Castles, gates and walls of Trieste: what remains of the fortified city

Talking about the castles, gates and walls of Trieste means telling the story of a city that for centuries lived enclosed behind a stone belt — and that today, to anyone walking through it, looks like a palimpsest. The walls have almost all fallen, the gates are ghosts swallowed by nineteenth-century buildings, and of the castles only two survive: one medieval, one romantic, staring at each other from opposite ends of the gulf.

From Tergeste to the Empire: the evolution of fortified Trieste

Trieste has been a walled town since antiquity. Already in 32 BC Augustus had the walls of Roman Tergeste rebuilt, and at the end of the fifth century AD they were restored again by Theodoric, king of the Ostrogoths. The Roman line ran where today the Jesuit church stands, with the sea lapping at its foot.

In the Middle Ages, when the city expanded along the slopes of San Giusto hill, an entirely new circuit was built — over three and a half metres thick, in sandstone, crowned with Guelph battlements, with square or polygonal towers, arrow slits, machicolations and round-arched gateways. Inside, blind arcatures housed workshops and small businesses. By the fourteenth century, as the so-called San Giusto altarpiece shows, the walls were a continuous defensive ring, completed by a wide moat fed by the Torrente San Michele and, on the seaward side, by sea water carrying small boats inland through the Portizza.

Maria Theresa and the great demolition

In 1719 Emperor Charles VI declared Trieste a Free Port. From that moment the medieval circuit became a brake on the city, which was filling up with new merchants, warehouses, consulates and shipyards. The decisive step came thirty years later: in 1749 the empress Maria Theresa ordered the gradual demolition of the walls. The chronicles register the stages with notarial precision — walls torn down near the Beccherie (today the police headquarters) in 1749, between Barbacan and the sea in 1750, between old town and new in 1752. The dismantling continued well into the nineteenth century: the Riborgo tower fell in 1784, the Clock Tower in 1838, the San Servolo tower in 1842, and the last great gate-towers as late as 1853.

The lost gates of Trieste

Of the medieval gates, almost none survives in its original form. The four main ones — Cavana, Riborgo, Donota, Portizza — opened onto the four cardinal points of the medieval city, and each defined a quarter.

Porta Cavana and the Portizza, the sea gates

Porta Cavana, in the fourth reconstruction of the walls (1471), opened toward the Sancti Martiri district and the fishermen's quarter. The very name Cavana comes from the Latin cavea, the hollow where boats were dragged ashore. Demolished progressively from the second half of the eighteenth century under Joseph II and then absorbed into the surrounding buildings, its remains were rediscovered in 2014 during ACEGAS waterworks excavations.

The Portizza, the small "harbour gate", controlled the Canal Piccolo, also called Canal del Vino, a navigable canal that ran from Riva Carciotti up to Piazza Vecchia. Filled in between the eighteenth and nineteenth centuries, the gate is now invisibly built into the buildings facing Piazza della Borsa, including the elegant Casa Bartoli designed by Max Fabiani.

Porta Riborgo and Porta Donota, the inland defence

On the opposite side of town, Porta Riborgo and Porta Donota formed a single fortified complex defending the road to the San Giusto hill. Each was crowned by a massive tower — pentagonal at Riborgo, square at Donota — with drawbridges and water-filled moats. The pattern of demolition was identical for both: the gates themselves were torn down in 1750, but the towers stood for another century before falling in 1853, during the great Habsburg redesign of Cittavecchia.

Tor Cucherna: the only medieval tower still standing

In the whole circuit, only one watchtower survived: Tor Cucherna, built in the fourteenth century by the Venetians for the night surveillance of the walls. About ten metres tall and five metres wide, it stood on the stretch of wall departing from the Rotonda Bastion of San Giusto castle. The name probably comes from the German gucken, "to peek", from which the Triestine dialect word cucar also derives.

The tower owes its survival to a happy mistake: when the medieval walls came down, the structure had already been swallowed by a private house and was used as a dwelling. In 1884 the historian Antonio Tribel noticed strange narrow openings — loopholes — in the façade, and the surrounding building was demolished to reveal the tower beneath. The restoration was completed in 1910 under the architect Enrico Nordio, then Conservator for Medieval Monuments, who rebuilt the upper part in red brick to distinguish it from the original sandstone.

Forte Kressich and the Habsburg defence of the port

By the mid-nineteenth century, walls and towers were obsolete: artillery had changed, and the threat to Trieste came from the sea. The Napoleonic occupations of 1797, 1806–1807 and 1809–1813 had exposed the city's vulnerability, and the Austrian High Command planned a modern coastal fortress to anchor a new defensive line.

The project was approved in 1850 by Emperor Francis Joseph, who entrusted its design to Karl Moering (1819–1870), Lieutenant Colonel of Engineers and amateur poet, of Prussian descent. Moering brought into the fort all the latest Prussian fortification techniques he had studied across the border. Built between 1854 and 1857 on the Poggio di Gretta at sixty metres above sea level, Forte Kressich combined:

• a long seaward bastion with reinforced loopholes
• a low circular rondella designed to withstand naval bombardment
• a wide dry moat with a counterscarp gallery and an internal caponiera
• underground passages and bomb-proof powder magazines, said to reach as far as the Barcola church

A garrison of more than a thousand men, armed with 48-pound cannons and later with Cavalli rifled breech-loaders, defended it.

When naval artillery outgrew the fort, Forte Kressich was downgraded to a military warehouse. In 1927 the Triestine architect Arduino Berlam built upon its main rondella the Faro della Vittoria, the Victory Lighthouse commemorating the Italian sailors of the Great War — a deliberate symbolic gesture, an Italian lighthouse rising on the foundations of a Habsburg fort.

The two surviving castles: San Giusto and Miramare

The two stone witnesses of imperial Trieste face each other across the gulf.

Castello di San Giusto: the imperial stronghold

The present Castello di San Giusto was begun in 1470 at the order of Emperor Frederick III of Habsburg, on the ancient acropolis of Tergeste. The new fortress had a polygonal plan, thick walls, angular towers and was intended to control both external threats and internal revolts. In 1508, during the war between Venice and the Empire, it was enlarged with the powerful Federiciana Tower at the entrance. The final curtain walls and bastions were added between 1630 and 1647, giving the castle its present irregular shape with central courtyard, ramparts and moat.

Castello di Miramare: the eclectic dream of Maximilian

The opposite pole of Habsburg Trieste rises at Grignano. In 1855 Archduke Ferdinand Maximilian of Habsburg, brother of Francis Joseph, decided to build himself a romantic residence facing the sea. He chose the site personally and commissioned the Austrian architect Carl Junker. The main body was completed between 1856 and 1860, in an eclectic neo-medieval style mixing Gothic, Renaissance and romantic references. Unlike San Giusto, Miramare was never a military building: it is a princely folly, a stage set for the imperial family that would soon include the tragic Mexican adventure of Maximilian himself.

What remains today

Of the great fortified Trieste, the visible traces are few but eloquent: Tor Cucherna and a stretch of the Federiciana wall in the Giardino del Capitano, the bastions of San Giusto, the silhouette of Miramare, the buried foundations of Forte Kressich under the Faro della Vittoria, and the names — Porta Cavana, Portizza, via di Donota, via di Riborgo — that toponymy still remembers. The medieval walls were demolished to make room for the modern, Habsburg, mercantile city. What survives is the imperial layer that came after — and the fragments that the city, by accident or by choice, refused to forget.