Gonio Fortress (Apsaros): Georgia's Roman Stronghold near Batumi

Gonio Fortress stands near the mouth of the Chorokhi River, about 15 kilometers south of Batumi in Adjara, on the coastal road toward the Turkish border, in the country of Georgia in the South Caucasus. Its rectangular stone walls rise from the flat coastal terrain in a way that immediately communicates the seriousness of its original military function. One of the oldest and best-preserved ancient fortifications in Georgia, it holds Roman, Byzantine, Ottoman, and Georgian layers accumulated across two millennia — which makes it one of the more historically substantial sites in Adjara, despite its modest scale beside the dramatic medieval fortresses found elsewhere in the country.

What is Gonio Fortress?

Gonio Fortress (known in antiquity as Apsaros) is a 1st-century AD Roman fort on Georgia's Black Sea coast, about 15 km south of Batumi near the Turkish border. Its rectangular walls (roughly 222 × 195 m, with 18 surviving towers of an original ~22) enclose an open archaeological site and a small museum, with Roman, Byzantine, and Ottoman layers. It's the oldest fortress in Georgia, tied by legend to Jason and the Argonauts, and by Orthodox tradition to the tomb of the Apostle Matthias. It's an easy half-day trip from Batumi, combined with the nearby beaches.

Roman origins: the fortress of Apsaros

Gonio was known in antiquity as Apsaros (Apsaros/Apsaruntos), and its origins as a significant military installation date to the Roman period, when it served as one of the easternmost garrison posts of the Roman Empire on the Black Sea coast. It's mentioned by Pliny the Elder in the 1st century AD, and by the 2nd century it was a well-fortified Roman town within Colchis, known to have had a theater and a hippodrome. The Romans recognized the strategic value of the location — at the mouth of the Chorokhi, near the edge of the empire's sphere of influence, on the route linking the Black Sea to the Caucasian interior — and built a fortress here of considerable scale and sophistication for its time. The walls, which stand to an impressive height along much of their circuit, preserve substantial sections of Roman construction alongside later Byzantine and Ottoman rebuilding, and the different periods are legible in the masonry to those who know how to read them. The site came under Byzantine influence, saw a short-lived Genoese trading presence, and was taken by the Ottomans in 1547; they held it until 1878, when Adjara passed to the Russian Empire.

The Argonaut legend

Gonio's ancient name ties it to one of the oldest stories associated with this coast. By legend, the name Apsaros derives from Apsyrtus (Apsyrtos), son of Aeëtes, the king of Colchis — the same king whose daughter Medea helped Jason and the Argonauts win the Golden Fleece. In the myth, Apsyrtus was killed during the Argonauts' flight and is said to have been buried at this site. It's legend rather than history, but it connects Gonio to the wider Colchis–Golden Fleece mythology of western Georgia — the same story commemorated by the Medea statue in Batumi's Europe Square and referenced by the Argo Cable Car.

The apostolic tradition: the tomb of St. Matthias

Gonio carries a religious significance that extends well beyond military history. According to Georgian Orthodox tradition, the fortress contains the tomb of Saint Matthias — the apostle chosen by lot to replace Judas Iscariot among the twelve — who is said to have traveled to the eastern Black Sea coast as part of the early Christian missionary expansion and to have died and been buried at Apsaros. The tradition is long-standing and the site receives pilgrims as well as historians. It's important to be clear, though, that the tomb is symbolic and unverified: it is marked within the fortress (large cross-stone pedestals stand at the spot, in the area of the Roman praetorium, the garrison commander's residence), but its location has not been demonstrated archaeologically, and the Georgian authorities currently prohibit excavation near the presumed gravesite. It's best understood as cultural and religious memory rather than a confirmed archaeological find.

The fortress

The outer walls form a rectangle of roughly 222 by 195 meters (a perimeter of about 900 meters, enclosing some 4.5 hectares), with towers at intervals along the curtain wall and at the corners — a layout characteristic of Roman military architecture that gave overlapping fields of fire from the towers and minimized blind spots in the defensive coverage. Eighteen towers survive today of an original twenty-two. The walls stand several meters high along most of their circuit, and walking the perimeter gives a clear sense of the scale and organization of the original garrison. The masonry quality varies — reflecting the different periods and resources across twenty centuries of construction and repair — but the overall impression is of a fortification built to last, which it largely has.

The interior is an open archaeological zone where excavations (ongoing since the 1990s) have uncovered evidence of occupation across multiple periods — Roman-era structures, Byzantine-period buildings, and later phases, in various states of excavation and preservation. A small on-site museum presents the most significant finds: pottery, coins, military equipment, and architectural fragments documenting the life of the garrison and the trading community that grew up around it. The grounds also feature ornamental planting, including floral designs of the Georgian and Adjaran flags.

The setting is worth noting. The flat coastal terrain, with the Chorokhi delta nearby and the Black Sea accessible from the walls, gives the site an openness and a connection to the natural geography that explains the Roman decision to fortify exactly here — it guarded the entrances to the Chorokhi and Acharistskali valleys, linking the interior of southwestern Georgia to the coast. The mountains of the Adjarian interior rise inland, and on clear days the Turkish coast is visible across the water to the south — a view the Roman commanders used to monitor coastal traffic much as a modern visitor uses it to get their bearings.

Getting there

Gonio is about 15 to 20 minutes from Batumi by car along the coastal road south toward the Turkish border. Marshrutkas and city buses running between Batumi and Sarpi pass through Gonio and stop near the fortress, so public-transport access is straightforward. The site is commonly included in organized tours of the Adjara coast and is easily combined with the Gonio and Kvariati beaches along the coastal road, or with the Botanical Garden north of Batumi for a fuller day out.

Practical information

• Location: Gonio village, Adjara, about 15 km south of Batumi on the coastal road (about 4 km north of the Sarpi/Turkish border).
• Hours: Daily, roughly 10:00–18:00 (may vary seasonally).
• Admission: Paid entry at the gate; the on-site museum is included. As a working archaeological museum-reserve, hours and access can change.
• Best to know: Some wall sections can be climbed for the view; bring sun protection (the site is open and exposed). Easily paired with the nearby beaches.