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Quick answer
Thessaloniki's monuments are visited in four different ways. The Rotunda, the White Tower and the Heptapyrgion are state monuments sold through Hellenic Heritage's official ticket store with timed entry, and the Museum of Byzantine Culture is sold there too. The Archaeological Museum of Thessaloniki publishes its own ticket-price and visiting-hours page. The Arch of Galerius stands on Egnatia Street and, according to the Ministry of Culture and Sports, has free admission. Saint Demetrius and Hagia Sophia are working Orthodox churches with their own websites, and the Ministry's portal describes an exhibition in the crypt of Saint Demetrius; the 5th-century Acheiropoietos is described by the Ministry, but XTOUR read no visiting page for it. UNESCO inscribed the Early Christian and Byzantine monuments of Thessaloniki in 1988 as one property made of many monuments; the Ministry groups twelve of them under that name, and the Arch of Galerius and the White Tower are not among the twelve. XTOUR states no hours, prices or travel times.
The short answer
Thessaloniki's Roman and Byzantine monuments are scattered through the modern city, and they are visited in four different ways.
- Ticketed state monuments. Hellenic Heritage's official ticket store sells timed-entry tickets for the Rotunda, the White Tower and the Heptapyrgion.[20][18][8]
- Museums. The same store sells the Museum of Byzantine Culture,[24] while the Archaeological Museum of Thessaloniki publishes its own ticket and visiting pages.[26]
- A monument on the street. The Arch of Galerius stands on Egnatia Street and, according to the Ministry of Culture and Sports, has free admission.[5]
- Working churches. Saint Demetrius and Hagia Sophia have their own church websites under the Holy Metropolis of Thessaloniki, each publishing a programme of services.[13][10] Beneath Saint Demetrius, the Ministry of Culture's portal describes an exhibition on display in the crypt.[11]
UNESCO inscribed the "Paleochristian and Byzantine Monuments of Thessalonika" on the World Heritage List in 1988, as one property.[1] That property is a group of separate buildings, not a single site with one gate, and the Ministry's own grouping under the same name leaves out the Arch of Galerius and the White Tower,[2] the two monuments the Ministry's page on the arch calls the best known in Thessaloniki.[4]
What the UNESCO listing covers
UNESCO's decision page records the inscription (decision 12 COM XIV.A, property 456, criteria i, ii and iv) but lists no components.[1] XTOUR could not open UNESCO's property page and has not read UNESCO's own component list.
The Ministry of Culture's Odysseus portal groups twelve monuments under "Early Christian and Byzantine monuments of Thessaloniki": the Rotunda, the churches of the Acheiropoietos, Saint Demetrius, Hagia Sophia, Panagia ton Chalkeon, the Holy Apostles, Saint Nicholas Orphanos and Saint Panteleimon, the Latomou Monastery, the Trigonion Tower, the Byzantine Bath and the Heptapyrgion.[2] Hellenic Heritage separately says the Heptapyrgion is listed as a UNESCO World Heritage Site.[19]
XTOUR's reading is that the Ministry's group is the closest official list it could read, not proof of which buildings UNESCO inscribed. The Arch of Galerius, the White Tower and the Galerian palace are not in the Ministry's group, and XTOUR does not say whether they belong to the property. Each monument XTOUR maps is kept as its own place, and none is presented as the UNESCO property itself.
Monuments by kind of visit
| Monument | What it is | How the official pages describe the visit |
|---|---|---|
| Arch of Galerius (Kamara) | Roman triumphal arch, 305 AD | According to the Ministry of Culture and Sports, free admission |
| Rotunda | Roman building of about 306 AD, later church and mosque | Hellenic Heritage ticket store, timed entry |
| Galerian palace | Archaeological site of Galerius's palace | Open to the public, per Hellenic Heritage; no online ticket link on its page |
| Saint Demetrius and its crypt | Working basilica; exhibition in the crypt | Church publishes its services; the Ministry's portal describes the crypt exhibition |
| Hagia Sophia | Working cathedral church | Church publishes its services |
| Acheiropoietos | 5th-century basilica | No visiting page read |
| White Tower | 15th-century tower with a city-history exhibition | Hellenic Heritage ticket store, timed entry |
| Heptapyrgion | Fortress, prison until 1989 | Hellenic Heritage ticket store, timed entry |
| Trigonion Tower | Tower of the walls | Fridays by appointment, per Hellenic Heritage |
| Museum of Byzantine Culture | State museum | Hellenic Heritage ticket store, timed entry |
| Archaeological Museum of Thessaloniki | State museum | Its own ticket and visiting page |
Roman Thessaloniki: the arch, the Rotunda and the palace
Galerius chose Thessaloniki as his seat in AD 299, according to Hellenic Heritage, and built a palace complex covering more than 150,000 m², which included the Rotunda, the triumphal arch known as Kamara, the palace itself, the Octagon and the hippodrome.[3] Today these are three separate visits.
The Arch of Galerius. The Ministry's Greek-language page says the arch was first an eight-pier gateway, with four massive central piers, four secondary ones and a low dome; two main piers and one secondary pier survive, joined by a brick arch. The narrative of its relief panels dates it to 305 AD, after Galerius's final victory over the Persians.[4] The Ministry's information page places it on Egnatia Street and lists it as free admission.[5]
The Rotunda. The Ministry's description says the Rotunda was built around 306 AD under Galerius, as a temple of Zeus or of the Kabeiros or, in other readings, as his mausoleum, and that a processional way from the arch to the palace ended on its axis. It became a church in the early Christian period, the Ministry says, at a date that is not known, probably dedicated to the Asomatoi or Archangels, and the mosaics in its dome and vaults belong to that phase; it was made a mosque in 1590/1 and was badly damaged in the earthquakes of 1978.[6] Hellenic Heritage adds that it was renamed the Church of Saint George in 1912.[7] Its ticket store sells the visit as "Rotunda (Church of St. George)" with timed entry, a single entry at the time chosen, changes up to two hours ahead and no refunds.[8]
The two official pages describe the building differently. Hellenic Heritage gives a diameter of 24 m and a height of 28 m, and says the conversions to worship "started in the second half of the 4th century BC".[7] The Ministry gives 24.50 m across and 29.80 m to the top of the dome, and dates the building itself to around 306 AD.[6] XTOUR's reading is that "BC" on the Hellenic Heritage page cannot be right for a building of the 4th century AD, and that the Ministry's own wording, that the conversion date is unknown, is the safer statement.
The palace. Hellenic Heritage says the palace is open to the public, and that its restoration won an award from the European Union and Europa Nostra. Its page lists a ticket but, unlike the Rotunda's page, carried no link to the online ticket store when read.[3] XTOUR has not read how palace tickets are sold.
Three churches and a crypt
The great Byzantine churches are first of all places of worship. XTOUR has not read any visiting rules, dress requirements or visiting times outside services from any of them, and does not supply any; for how working churches and monasteries differ as visits in Greece, see Greek Orthodox monasteries as visits.
Saint Demetrius. The Ministry describes a five-aisled basilica with a crypt under its sanctuary and transept, and traces it from a small oratory built shortly after 313 AD over a Roman bath, to a 5th-century basilica founded by the eparch Leontios and burnt in 626-634, to the five-aisled church that followed. It was a mosque from 1493, was returned to Christian worship in 1912, burnt in the great fire of 1917, and functioned again from 1949.[9] The church's own website, published under the Holy Metropolis of Thessaloniki, dates Leontios's church to "the middle of the 5th century (413)", which in XTOUR's reading does not match its own "middle of the century", and says the ancient bath where the saint was held was kept as the crypt, which "remains a centre of worship".[10] The Ministry's crypt page says the crypt has been an archaeological site since its discovery in 1918 and holds an exhibition of early Christian and Byzantine sculpture rescued from the 1917 fire and finds from the 1985-1988 excavations.[11]
Hagia Sophia. The Ministry's Greek-language page says the church was built at the end of the 7th century on the site of a 5th-century basilica destroyed by an earthquake around 620, and that its first written mention dates from 795. It was the Latin cathedral in 1204-1224, the Orthodox see again until 1523/24, then a mosque, and it was reconsecrated for Christian worship on 29 June 1913. The same page dates the Ascension mosaic in the dome to the late 9th century.[12] The church's own website calls it the cathedral and pilgrimage church of the Holy Metropolis of Thessaloniki, near the Acheiropoietos.[13]
The Acheiropoietos. On Agias Sofias Street, north of Hagia Sophia, the Ministry describes a three-aisled, timber-roofed basilica with galleries from around the middle of the 5th century, built over a Roman bath, with 5th-century mosaics and early 13th-century wall paintings. The same page says the name Acheiropoietos is first recorded in 1320, and that the church was the first converted into a mosque after the Ottoman capture of 1430, known as Eski Cami.[14] In 1913, the Museum of Byzantine Culture's history records, a decree planned to house a Central Byzantine Museum in this church.[21]
The fortifications: White Tower, Heptapyrgion and Trigonion
The White Tower. The tower's own website says it was built in the 15th century, after the Ottoman capture of 1430, where the eastern land wall met the sea wall, on the site of an older Byzantine tower. It was the Lion Tower in the 16th century, the Tower of Kalamaria in the 18th, and the Tower of Blood when it served as a prison and place of execution, until it was painted white in 1883 on the orders of Sultan Abdul Hamid II. Since 1911, when the walls around it were demolished, it has stood alone on the shore.[15]
Inside is a permanent exhibition on Thessaloniki from its founding in 316/15 BC to the present. The website says the tower's limited space and need for a stable climate cap the number of visitors inside at once at 70 and leave no room for toilets, a cloakroom or baggage storage.[16] The tower is tied to the Museum of Byzantine Culture: a 1999 ministerial decision placed the museum at both 2 Stratou Avenue and the White Tower,[21] and Hellenic Heritage lists the museum as a contact for the tower.[17] The ticket store sells the tower separately from the museum, with timed entry.[18]
The Heptapyrgion and the Trigonion Tower. Hellenic Heritage presents the two on one page but as two visits. The Heptapyrgion, or Yedikule, is the fortress at the north-eastern end of the walls; it was a prison from 1890 until 1989, when it passed to the Ministry of Culture, and is open to the public today.[19] Its ticket store sells it with timed entry.[20] The Trigonion Tower has its own address, and Hellenic Heritage says it is "open to visitors every Friday by appointment", arranged by telephone with the Ephorate of Antiquities of the City of Thessaloniki.[19]
The two museums
Museum of Byzantine Culture. It opened on 11 September 1994 with an exhibition that marked the return to Thessaloniki of Byzantine antiquities taken to the Byzantine and Christian Museum in Athens in 1916, according to its history page; the building is by Kyriakos Krokos.[21] Hellenic Heritage says its eleven halls show Byzantine and post-Byzantine culture through finds mainly excavated in Thessaloniki and wider Macedonia, and that the Council of Europe named it "Museum of Europe" in 2005.[23] The museum's visit page says groups visit after telephone confirmation and that visiting hours are subject to change without notice.[22]
Archaeological Museum of Thessaloniki. Its collections run from the prehistoric era to the end of antiquity, from excavations across Macedonia since 1912, according to the museum, and its building by Patroklos Karantinos, begun in 1960, is a listed monument.[25] Hellenic Heritage names the bronze volute krater of Derveni among the exhibits and describes an outdoor area of sarcophagi and funerary monuments.[27] The museum's own page says groups visit after telephone confirmation, and that hours can change without notice.[26] It is a separate museum from the Museum of Byzantine Culture, which covers the later periods.[23]
What XTOUR does not know
XTOUR does not publish opening hours, prices, closing days or walking times for any of these monuments; Hellenic Heritage and the two museums publish hours and prices on their own pages. It does not know UNESCO's own list of components, the visiting arrangements of the three churches outside services, how Galerian palace tickets are sold, or whether the Acheiropoietos and the smaller churches in the Ministry's group keep set visiting times. For the city as a base, see the Thessaloniki destination page; for the royal tombs at Vergina, a separate place outside the city, see Aigai and the royal tombs.
Sources & references
- [1]UNESCO World Heritage Centre, Decision 12 COM XIV.A, 'Inscription: Early Christian and Byzantine monuments of Thessalonika (Greece)': property 456, 'Paleochristian and Byzantine Monuments of Thessalonika', criteria C(i)(ii)(iv), 12th session of the World Heritage Committee, 1988; the page gives no component list. Read 2026-10-09
- [2]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Early Christian and byzantine monuments of Thessaloniki', site monuments tab: Rotonda, Church of Acheiropoiitos, Church of Agios Dimitrios, Monastery of Latomou, Church of Agia Sophia, Panagia ton Chalkeon, Church of Agioi Apostoloi, Church of Saint Nicolaos Orfanou, Church of Agios Panteleimon, Trigonion Tower, Byzantine Bath, Heptapyrgion; the group's history and description tabs say 'not available'. Read 2026-10-09
- [3]Hellenic Heritage (hh.gr, operated by ODAP), 'Galerian Complex in Thessaloniki: The palace of Emperor Galerius': Galerius chose Thessaloniki as his seat in AD 299; the palace complex extended over 150,000 m2 and included the Rotunda, the Triumphal Arch (Kamara), the Palace, the Octagon and the Hippodrome; 'Today, the Palace is open to the public', awarded by the European Union and Europa Nostra for its restoration; address Navarinou Square; contact Ephorate of Antiquities of the City of Thessaloniki; the page lists a ticket but carries no link to the online ticket store. Read 2026-10-09
- [4]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Αψίδα Γαλερίου' (Arch of Galerius), Greek-language description: called Kamara today; originally an eight-pier gateway with four main and four secondary piers and a low dome; two main piers and one secondary pier survive, joined by a brick arch; built in 305 AD, as the narrative of its relief panels shows, after Galerius's final victory over the Persians; Thessaloniki the capital of the caesar Galerius under the First Tetrarchy; the page opens by calling the arch, together with the White Tower, the best-known monument of Thessaloniki. Read 2026-10-09
- [5]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Triumph Arch of Galerius' information page: Egnatia Str., Thessaloniki; contact efapoth@culture.gr; Tickets 'Free admission'; the English description tab says 'The description is not available'. Read 2026-10-09
- [6]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Ροτόντα, Θεσσαλονίκη' (Rotunda), Greek-language description: built in the years of the caesar Galerius around 306 AD as a temple of Zeus or of the Kabeiros or, by other accounts, his mausoleum; a processional way linking Galerius's triumphal arch with the palace ended on its axis; diameter 24.50 m, dome rising to 29.80 m, wall 6.30 m thick; converted into a Christian church, probably of the Asomatoi or Archangels, in the early Christian period, 'unknown exactly when'; mosaics of the early Christian phase in the dome and vaults; mosque in 1590/1; serious damage in the 1978 earthquakes and restoration since. Read 2026-10-09
- [7]Hellenic Heritage (hh.gr, operated by ODAP), 'Rotunda: An enigmatic monument with magnificent mosaics': built in Galerius's reign as a pagan temple or his mausoleum; its transformations into a place of worship 'started in the second half of the 4th century BC'; walls 6.30 m thick, height 28 m, diameter 24 m; early Byzantine mosaics; renamed 'Church of Saint George' in 1912; address 5 Agiou Georgiou Square; contact Ephorate of Antiquities of the City of Thessaloniki. Read 2026-10-09
- [8]Hellenic Heritage Tickets (tickets.hh.gr, ODAP), 'Rotunda (Church of St. George) Tickets': 'Official ticket store'; Digital Guide app included; 'Timed entry required'; single entry on the selected date and time; changes up to 2 hours before the visit, at most two; non-refundable; reduced or free tickets need ID; large luggage, food, professional photo shooting or filming not permitted; product 'Visit the Rotunda (Church of Saint George)'. Read 2026-10-09
- [9]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Church of Agios Dimitrios': five-aisled basilica with narthex and transept, crypt under the sanctuary and transept; first a small oratory shortly after 313 AD on the ruins of a Roman bath; in the 5th century the eparch Leontios founded a three-aisled basilica, burnt in 626-634, followed by the five-aisled basilica; mosque in 1493, restored to Christian worship in 1912, destroyed in the great fire of 1917, rebuilt and functioning again in 1949; an exhibition on display in the crypt. Read 2026-10-09
- [10]Holy Church of Saint Demetrius, Patron of Thessaloniki (agdimitriosthes.gr, Holy Metropolis of Thessaloniki), 'Ναός' page, Greek: short history: the church was built 'in the middle of the 5th century (413)' on the place of the saint's martyrdom by Leontios, eparch of Illyricum; the ground-floor complex of the ancient bath where the saint was imprisoned was kept and adapted as the crypt, 'which became and remains a centre of worship'; the site publishes a programme of services. Read 2026-10-09
- [11]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Crypt of Agios Demetrios, Thessaloniki': an archaeological site since its discovery in 1918; excavations in the north part in 1985-1988 and an exhibition of the excavation finds and the antiquities rescued from the 1917 fire, the page not naming who runs it; early Christian sculpture of the 5th to 7th centuries, Byzantine sculpture of the 11th to 14th centuries, coins and pottery. Read 2026-10-09
- [12]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Ναός Αγίας Σοφίας' (Church of Hagia Sophia), Greek-language description: at the junction of Agias Sofias and Ermou streets; earliest written mention 795, built at the end of the 7th century on the site of a 5th-century five-aisled basilica destroyed by earthquake around 620; Latin cathedral 1204-1224, Orthodox see again until 1523/24, then a mosque; damaged by fire in 1890, restored 1907-1909 by the Byzantinist Charles Diehl; reconsecrated for Christian worship on 29 June 1913; Ascension mosaic in the dome of the late 9th century. Read 2026-10-09
- [13]Holy Cathedral Church of the Wisdom of God, Thessaloniki (agiasofia.info), Greek home page: the cathedral and pilgrimage church of the Holy Metropolis of Thessaloniki, in the centre near the church of the Panagia Acheiropoietos; with Saint Demetrius and the Acheiropoietos among the most important early Christian monuments; the site publishes a programme of services. Read 2026-10-09
- [14]Hellenic Ministry of Culture and Sports, Odysseus portal, 'Αχειροποίητος' (Acheiropoietos), Greek-language description: on Agias Sofias Street, north of Hagia Sophia; built around the middle of the 5th century; three-aisled timber-roofed basilica with galleries, over the ruins of a Roman bath; 5th-century mosaics and early 13th-century wall paintings; called in written sources the great church of the Theotokos, the name Acheiropoietos first recorded in 1320; the first church converted into a mosque after the capture of the city in 1430, known as Eski Cami. Read 2026-10-09
- [15]White Tower of Thessaloniki official website (lpth.gr), history page: built in the fifteenth century after the Ottoman capture of 1430, where the eastern wall met the sea wall, replacing an older Byzantine tower; called the Lion Tower (16th century), the Tower of Kalamaria (18th), the Tower of the Janissaries and the Tower of Blood (19th); painted white and named White Tower in 1883 on the orders of Sultan Abdul Hamid II, whitewashed by the convict Nathan Guiledi; stood alone on the shore from 1911 after the walls were demolished. Read 2026-10-09
- [16]White Tower of Thessaloniki official website (lpth.gr), home page: permanent exhibition on Thessaloniki from its founding in 316/15 BC to the present; the limited space and the need for stable climatic conditions impose 'a limited number of visitors at the same time (maximum 70)' and rule out toilets, snack bar, cloakroom and baggage storage; virtual tour at ground-floor stations for people with limited mobility; audio tour in four languages. Read 2026-10-09
- [17]Hellenic Heritage (hh.gr, operated by ODAP), 'White Tower: The ultimate Thessaloniki landmark': typed Monument, Museum; built where the coastal and eastern land walls met, a 15th-century building that replaced an earlier Byzantine structure; height 33.90 m, diameter 21.70 m, six storeys and a ground floor; restoration of 1985 by the Ephorate awarded the Europa Nostra Prize in 1988; contacts The White Tower and the Museum of Byzantine Culture. Read 2026-10-09
- [18]Hellenic Heritage Tickets (tickets.hh.gr, ODAP), 'White Tower of Thessaloniki Tickets': 'Official ticket store'; 'Timed entry required'; single entry on the selected date and time; changes up to 2 hours before, at most two; non-refundable; product 'Visit the White Tower'. Read 2026-10-09
- [19]Hellenic Heritage (hh.gr, operated by ODAP), 'Heptapyrgion and Trigonion Tower': the Heptapyrgion fortress ('Yedikule') at the north-eastern end of the Thessaloniki walls, a prison from 1890 until 1989, when it passed to the Ministry of Culture; 'Today, it is open to the public and is listed as a UNESCO World Heritage Site'; the Trigonion Tower 'open to visitors every Friday by appointment', by telephone to the Ephorate; separate addresses (40 Eptapyrgiou St; Eleftheriou Venizelou and Eptapyrgiou Sts); contact Ephorate of Antiquities of the City of Thessaloniki. Read 2026-10-09
- [20]Hellenic Heritage Tickets (tickets.hh.gr, ODAP), 'Heptapyrgion, Thessaloniki Tickets': 'Official ticket store'; Digital Guide app included; 'Timed entry required'; product 'Visit Heptapyrgion'. Read 2026-10-09
- [21]Museum of Byzantine Culture (mbp.gr), history page: opened 11 September 1994 with the exhibition 'Byzantine Treasures of Thessaloniki. The return journey', marking the return of antiquities taken to the Byzantine and Christian Museum in Athens in 1916; a 1913 decree had planned a Central Byzantine Museum housed in the Acheiropoietos church; building designed by Kyriakos Krokos after a 1977 competition, completed 1993; a 1999 ministerial decision made it a Special Regional Service hosted at 2 Stratou Avenue and the White Tower. Read 2026-10-09
- [22]Museum of Byzantine Culture (mbp.gr), visit page: groups visit after telephone confirmation; 'Visiting hours are subject to change without notice'; reduced admission 'to the Museum of Byzantine Culture and the White Tower'; audio guides and a museum app in twelve languages including Greek Sign Language. Read 2026-10-09
- [23]Hellenic Heritage (hh.gr, operated by ODAP), 'Museum of Byzantine Culture Thessaloniki': building by Kyriakos Krokos built 1989-1993 and listed; eleven halls of Byzantine and post-Byzantine culture with exhibits mainly excavated in Thessaloniki and wider Macedonia; 'Museum of Europe' title from the Council of Europe in 2005. Read 2026-10-09
- [24]Hellenic Heritage Tickets (tickets.hh.gr, ODAP), 'Museum of Byzantine Culture Tickets': 'Official ticket store'; 'Timed entry required'; single entry on the selected date and time; non-refundable; product 'Visit the Thessaloniki Museum of Byzantine Culture'. Read 2026-10-09
- [25]Archaeological Museum of Thessaloniki (amth.gr), 'Museum' page: collections from the Prehistoric era to the end of antiquity, from excavations throughout Macedonia since 1912 and handed-in antiquities; construction began in 1960 near the International Trade Fair grounds to a design by Patroklos Karantinos; a listed monument; the Ephorate of Antiquities founded in November 1912. Read 2026-10-09
- [26]Archaeological Museum of Thessaloniki (amth.gr), 'Ticket prices and visiting hours': 'Visiting hours are subject to change without notice'; groups can visit after confirmation by telephone on weekdays. Read 2026-10-09
- [27]Hellenic Heritage (hh.gr, operated by ODAP), 'Archaeological Museum of Thessaloniki': six permanent exhibitions from prehistory to late antiquity; the bronze volute krater of Derveni, 4th century BC, from Tomb B of the Derveni necropolis; outdoor area with sarcophagi, burial monuments and a model of an Imperial-era house; building by Patroklos Karantinos, a listed monument; the page carries no link to the online ticket store. Read 2026-10-09
Frequently asked questions
Good to know
Is the Rotunda a church or a museum?
Both histories apply. According to the Ministry of Culture's Odysseus page, the Rotunda was built around 306 AD under Galerius, became a Christian church in the early Christian period and was made a mosque in 1590/1. Hellenic Heritage says it was renamed the Church of Saint George in 1912. Today Hellenic Heritage's ticket store sells timed-entry tickets for it, under the name 'Rotunda (Church of St. George)', and its contact is the Ephorate of Antiquities of the City of Thessaloniki.
Is Thessaloniki's Hagia Sophia the same building as Hagia Sophia in Istanbul?
No. The Ministry of Culture's page describes Thessaloniki's Hagia Sophia as a domed church built at the end of the 7th century at the junction of Agias Sofias and Ermou streets in Thessaloniki, on the site of a 5th-century basilica. Its own website calls it the cathedral church of the Holy Metropolis of Thessaloniki.