On the hill of San Giusto, most visitors do the same thing: they take bus 24 up, photograph the castle, walk into the cathedral, glance at the apse straight ahead and come back down a quarter of an hour later. In that quarter of an hour they have looked at the wrong mosaic.
The central apse, the one you see as soon as you walk in and the one that catches the eye because it is the largest and the best lit, is from 1932. The two mosaics worth the trip are in the side apses, tucked away, one to the right and one to the left of the presbytery, and they are eight centuries older. The pillar guide to what to see in Trieste mentions them in a single paragraph. This article is that paragraph, opened up.
Note: if you are climbing the hill for the bell tower, check the month. From April to September you can go up every day, in March and October only in two time slots, but in the winter months the climb is by appointment only, arranged by phone with the parish. Anyone who turns up in January expecting to climb will not be climbing. There is also ongoing building work on the hill affecting traffic and parking, so if you are coming by car, factor that in.
Three thousand years in a hundred metres: what came before
The hill is not the place where they built the cathedral. It is the place where Trieste built everything, one layer on top of another, for three thousand years, and the cathedral is simply the layer that shows best. From the ramparts you can also take in the rest of the city in a single glance: the regular grid opening towards the sea did not grow on its own, it is the Borgo Teresiano, laid out in the eighteenth century over the reclaimed salt pans.
Underneath there was a prehistoric hillfort. After the middle of the 1st century AD the Romans placed the two main buildings of Tergeste there: a civil basilica, that is the city’s law court and merchants’ exchange, and a monumental colonnaded entrance, the propylaeum, which closed off a walled sacred precinct where the Capitoline temple is thought to have stood.
The size of the civil basilica shows how large the city was: more than twenty metres wide and almost a hundred deep. Today what remains are two rows of column stumps on the paving in front of the church, plus two brick shafts put back upright. Everything else vanished in the 5th century, when it was quarried for material for the Christian hall built a few metres away, turned ninety degrees relative to the Roman basilica.
That 5th-century hall has left us its mosaic floors, and this is the oldest part you can still walk on. In 547 a bishop named Frugifer, the first bishop of Trieste we know by name, had it restored and added the apse: an inscription records it, and his monogram can still be read on some of the small columns in the right aisle.
Two churches, six aisles, one demolition
Why does a cathedral have five aisles when none of them seem aligned with the others? Because it was not born as a cathedral: it was born as two separate churches, facing each other across the main street, and someone later decided to stitch them together.
To the north stood the episcopal basilica of Santa Maria Assunta, with three aisles, a direct descendant of the early Christian hall. To the south, facing it, stood the shrine of San Giusto, the patron martyr, built to hold his relics and likewise developed into a three-aisled church. Between the two ran the street that climbed up from the sea.
Between 1302 and 1320 the bishop Rodolfo Pedrazzani da Robecco wanted a single, imposing cathedral, and he got it by the most brutal method available: he had the right aisle of the Assunta and the left aisle of the shrine demolished, and in the space that was freed up he built a new aisle. Six aisles minus two plus one makes five, and that is exactly the arithmetic that explains today’s floor plan.
This is why the five aisles are asymmetrical in length and in the spacing of their columns, and why, walking through, you never find a single axis that holds all the way to the far end. It is not a flaw in medieval workmanship: it is the scar of the stitching, and it is the most interesting thing about the plan.
The practical consequence is that the two ancient churches can still be made out, and it is worth walking them as such. The right aisle is the old shrine of San Giusto, with its small cupola over a ring of little arches and its thirteenth-century frescoes. The left aisle, today dedicated to the Blessed Sacrament, is the main aisle of the old Santa Maria. Anyone who walks straight in towards the high altar cuts across both of them.
The façade, where a Roman matron became a saint
The façade is built of sandstone, austere to the point of severity, and allows itself only one flourish: the Gothic rose window in Karst stone, six metres seventy across, with a double ring of small colonnettes and tracery. Local tradition credits it to stonecutters brought in from Soncino, near Cremona, the area the bishop came from, and Trieste still keeps the memory in the name of Via dei Soncini.
Everything else on the façade is reused Roman material, and not discreetly so. The bronze busts of three notable bishops, added in 1862, rest on brackets carved from Roman pedestals. Among the three is Enea Silvio Piccolomini, bishop of Trieste before he became Pope Pius II.
The showpiece, though, is the jambs of the central portal. They are the two halves of a Roman funerary stele belonging to the Barbia family, sawn lengthwise and set upright on either side of the door. On each half you can still read the portraits of the deceased in their niches and the inscriptions with their names, BARBIAE OPTATAE FILIAE among others.
And here is the detail that rewards the stop. In the lower right panel is a portrait of Tullia Secunda, a Roman woman, with her name carved beneath. At some unknown point someone added a halo behind her head and a halberd resting on her shoulder: the halberd is the emblem of Trieste and the attribute of Saint Sergius, and the matron became a male saint without her face changing. The carved name stayed the same as before.
The bell tower: a Roman temple inside, a war outside
What is a monumental Roman entrance doing inside a fourteenth-century bell tower? It ended up there because the tower was built around it, not next to it: in 1337 the old Santa Maria’s tower was clad with a thick wall to bear the weight of the new church, and that wall enclosed the propylaeum, which had been standing since roughly 50 AD. The work finished in 1343.
The propylaeum was the gateway to the upper town, at the top of the road that climbed from the harbour, and it measured over seventeen metres wide. Restored in 2020, it still stands upright, with its base, fluted columns and attic in place, and archaeologists rate it as a unique case north of Rome for this level of preservation. Part of it can be seen from outside through a grating; the other half, with the stairway that once linked the two wings, can be visited by going down beneath the square from the Orto Lapidario of the Winckelmann Museum.
On the outer side, at eye level, runs a Roman frieze with scrolling vine motifs reused as a cornice, and above it a Gothic niche opens with a thirteenth-century statue of San Giusto: he holds the martyr’s palm in one hand and a model of the walled city in the other. Look at the head against the body. It is out of scale, because it comes from another sculpture and was reassembled here.
The bell tower used to be taller. In 1422 lightning struck it and it was reduced to its present height, which is why it now looks squat against the bulk of the church.
Look next, in the masonry, for the cannonballs still lodged there. They were fired during the Austro-British bombardment of 1813 against the Napoleonic troops holed up in the castle. The war left a second mark, and this one is heard rather than seen: the Campanon, the largest bell, was recast in 1829 using the bronze of cannon abandoned by the French. The same artillery, first in the wall, later in the sound of the bells.
The Theotokos: the mosaic that stands between Ravenna and Venice
Why does this mosaic look at once like Ravenna, Venice and Sicily? Because scholars disagree about who made it, and all three theories hold up when you actually look at the wall.
In the vault of the left apse, on a gold ground, the Theotokos, the Virgin, sits enthroned with the Child on her lap, flanked by the archangels Michael and Gabriel holding the orb and the labarum. The current dating is the first half of the 12th century and the composition follows a Constantinopolitan model: the absolute frontality, the blue drapery in stiff folds, the fixed gesture.
Below the vault runs the band of the twelve apostles, and that is where the picture gets more complicated. They do not stand on a gold ground: they walk across a flowering green meadow, with their feet on the grass and small white and red flowers between their legs. That meadow is not Byzantine, it is Ravennate: it is the same decorative scheme used in the apse of Sant’Apollinare in Classe, the mosaic that closes any visit to what to see in Ravenna.
Scholars assign the band of apostles to a Venetian workshop, trained on the building site of St Mark’s Basilica in the last quarter of the 11th century, and they find the same hand in Ravenna’s Ursiana cathedral and in Santa Maria Assunta at Torcello. The booklet on sale at the church entrance instead proposes another connection, to the Siculo-Byzantine mosaics of Cefalù cathedral, and by extension to the Norman workshop responsible for the Palatine Chapel in Palermo.
This is not a specialists’ quarrel: it is the reason Trieste matters. In the 12th century, Byzantine mosaic in Italy is made in three places, Venice, Ravenna and Norman Sicily, and almost no guidebook mentions the fourth. The fourth is here, in a side apse that almost everyone walks past without turning their head.
The Pantocrator, and the Christ who tramples the serpent
The right apse, the one belonging to the old shrine, holds the second mosaic, and it belongs to a different generation: sources place it around 1210, the work of Byzantine mosaicists.
At the centre, standing rather than enthroned, is Christ Pantocrator: slender, severe, the book in his left hand, his right hand raised in blessing. On either side, arranged as in a deesis, are the city’s two patron saints, San Giusto with the palm and San Servolo. The composition is more austere than that of the Virgin and the figure of Christ is more elongated, which is the detail the later dating rests on.
Look at the feet. Christ is not resting on a carpet or a cloud: he stands upright on a footstool, beneath which two crushed creatures are depicted, the asp and the basilisk. It is the literal illustration of Psalm 90, super aspidem et basiliscum ambulabis, and in the thirteenth century it told anyone entering something precise: evil has already been trampled, it is not an ongoing threat.
Along the lower edge of the vault runs a Latin inscription that binds the two saints together as a pair, wishing whoever lives in harmony with them to be blessed together. In context it carries a political meaning alongside the devotional one, because Giusto and Servolo were two separate local martyrs, and that mosaic declares them inseparable at the very moment the city was about to merge their two churches.
The 5th-century floor and the apse that dates from 1932
Go back to the centre of the church and look down. Between the chairs and the modern floor, fragments of the 5th-century early Christian mosaic surface, with geometric and floral motifs in white, red and black tesserae. They are the remains of the hall that stood here before everything else, brought to light by excavations carried out between 1949 and 1952, and traces of them also survive in the left aisle.
Now look up towards the central apse, the one you looked at on your way in. It is modern, and its history is a chain of replacements. In 1423 two Friulian artists, Domenico Lu Domine and Antonio Baietto, painted a Coronation of the Virgin there. In 1843 the apse was enlarged, the fresco was destroyed and a neoclassical coffered vault took its place; some fragments of the fresco are kept at the castle.
In the early 1930s the apse was demolished and rebuilt again, and the coffered decoration gave way to a mosaic reprising the same subject from five centuries earlier. It was made by the Venetian Guido Cadorin in 1932, showing the Coronation of the Virgin and the martyrs of Trieste, with the stated intention of giving continuity to the two medieval mosaics in the side apses.
The Latin inscription beneath the ceiling says something else, though, and says it without mincing words: the people of Trieste raised this work rejoicing at having been welcomed into the bosom of Mother Italy, in the fourteenth year. The fourteenth year is counted from 1918, that is, from the city’s annexation to Italy. That mosaic is a political monument, and anyone who looks at it knowing this sees a page of twentieth-century history rather than a generic backdrop.
Below it hangs the chandelier, made of crystal by a Bohemian workshop, with an unexpected history: it was originally destined for the throne room of Maximilian of Habsburg, the brother of Franz Joseph who left Miramare to become Emperor of Mexico and was executed at Querétaro in 1867. After that end, Franz Joseph donated it to the cathedral.
The castle, a fortress that has almost never fought
Thirty steps from the façade begins the Castle of San Giusto, and it is worth seeing it for what it is: a system of ramparts grown over three centuries around a Venetian core.
The first castle was built by the Venetians between 1368 and 1371. It then passed to the Habsburgs, who extended it steadily in three phases: the Lalio bastion to the southeast between 1551 and 1561, the northern curtain wall in 1595 and the last bastion, Pomis, in 1630. You can walk along the sentry walk, and from up there you take in the gulf, the roofs of the city and the hill all at once.
In the seventeenth century there was a plan to rebuild the fortress from scratch, extending it across the whole top of the hill. Carried out to the letter, it would have meant demolishing the cathedral, and buried foundations of a fourth bastion that was never built have been found beneath the basilica. The plan died on its own after the French bombardment of 1702, when it became clear that a huge fortress on that hill was no longer needed. The drawings for that plan are kept in Ljubljana, a little over an hour and a half from Trieste: if you have a spare day, the guide to what to see in Ljubljana starts right there.
And here is the fact that puts the castle back in perspective. Throughout its entire existence, this fortress, built explicitly for war, was used by the military twice. The first time in 1813, when Napoleon’s troops held out here for two weeks under siege by the Austrian, British and Neapolitan fleets, the episode that left the cannonballs in the bell tower. The second in 1945, when the Germans surrendered here to the liberating forces. Between the two episodes lie a hundred and thirty-two years of nothing.
The ticket includes the Armoury, with a collection of edged and firearms weapons, and the Lapidario Tergestino, opened in 2001 on the Lalio bastion, where Roman inscriptions, sculptures and architectural fragments are gathered: many of them come from the very buildings on the hill of which only the column stumps survive above ground.
Practical information
Data verified on 4 September 2026 on the official sites of the parish of San Giusto and the Municipality of Trieste. Prices and hours change: check again before you travel.
Tickets. Entry to the cathedral is free, and a donation is welcome. The castle costs 7 euros full price and 5 concession, and the ticket includes the walls and bastions, the Civic Museum of the Castle of San Giusto with the Armoury, the Lapidario Tergestino and the temporary exhibitions held at the Bastione Fiorito. School groups pay 1 euro per student.
Cathedral opening hours. On weekdays it opens 8 am to 6.30 pm, and on Sundays and public holidays 9 am to 7.30 pm, with no midday closure.
Bell tower opening hours. From April to September you can go up every day, 9 am to 5.30 pm. In March and October you can go up every day, 9 am to noon and 2.30 pm to 5 pm. In the winter months, the climb is by appointment only, arranged by calling the parish.
Castle opening hours. Until 11 October it opens every day 10 am to 7 pm, with last entry at 6.30 pm. From 12 October it opens Tuesday to Sunday, 10 am to 5 pm, with last entry at 4.30 pm, so in winter it is closed on Mondays. It stays closed on 25 December and 1 January.
Free admission. The castle can be visited free of charge on the first Sunday of the month and on 3 November, the feast of the patron saint.
Accessibility. People with disabilities can access the castle from Via della Rimembranza, and the lift is activated on request.
Getting there. Bus 24 climbs the hill from the waterfront and spares you the walk up. On foot from the centre it is about a twenty-minute climb, either along Via della Cattedrale or up the Scala dei Giganti. Note: building work is under way on the hill affecting road access and parking, so a car is the worst option.
How much time to allow. The cathedral alone needs forty minutes, if you really look for the two apses and the floor. With the bell tower and the castle the whole morning fills up: allow two and a half hours in total, plus whatever time you spend on the ramparts looking at the gulf.
Photo credits: cathedral from the roman forum by Stefan Vladuck, early christian floor by Kritzolina, Cadorin apse by Gianfrii, castle from the forum by Zairon (CC BY-SA 4.0); frieze and statue on the bell tower by Matthias Kabel, propylaeum columns and stele of Tullia Secunda by Wolfgang Sauber (CC BY-SA 3.0); civil basilica, naves and apse mosaics by Sailko (CC BY 3.0); rose window by Andrek02 (CC0). All from Wikimedia Commons.
