Gonio fortress (previously called Apsaros, or Apsaruntos), is a Roman fortification in Adjara, at the mouth of the Chorokhi river. The oldest reference to the fortress is by Pliny the Elder in the Natural History (1st century AD). There is also a reference to the ancient name of the site in Appian’s Mithridatic Wars (2nd century AD). In the 2nd century AD it was a well-fortified Roman city within Colchis. The town was also known for its theatre and hippodrome. It later came under Byzantine influence. The name 'Gonio' is first attested in Michael Panaretos in the 14th century. In addition, there was a short-lived Genoese trade factory at the site.
In 1547 Gonio was taken by the Ottomans, who held it until 1878, when, via the San-Stefano Treaty, Adjara became part of the Russian empire. In the fall of 1647, according to Evliya Çelebi, Gonio was captured by a Cossack navy of 70 chaikas, but quickly recovered by Ghazi Sidi Ahmed, ruler of the Tortum sanjak, with a force of 1,000 Turks and 3,000 'Mingrelians'.
The grave of Saint Matthias, one of the twelve apostles, is believed to be inside the Gonio fortress. However, this is unverifiable as the Georgian government currently prohibits digging near the supposed gravesite. Other archaeological excavations are however taking place on the grounds of the fortress, focusing on Roman layers.
References:The Church of St Eustace was built between 1532-1632. St Eustace"s is considered a masterpiece of late Gothic architecture. The church’s reputation was strong enough of the time for it to be chosen as the location for a young Louis XIV to receive communion. Mozart also chose the sanctuary as the location for his mother’s funeral. Among those baptised here as children were Richelieu, Jeanne-Antoinette Poisson, future Madame de Pompadour and Molière, who was also married here in the 17th century. The last rites for Anne of Austria, Turenne and Mirabeau were pronounced within its walls. Marie de Gournay is buried there.
The origins of Saint Eustache date back to 13th century. The church became a parish church in 1223, thanks to a man named Jean Alais who achieved this by taxing the baskets of fish sold nearby, as granted by King Philip Augustus. To thank such divine generosity, Alais constructed a chapel dedicated to Sainte-Agnès, a Roman martyr.