Gonio-Apsaros (a Byzantine castle Ten miles south of town with a crenelated wall which now guards a courtyard of citrus trees) and the detritus of stone Roman waterworks (scattered under a magnolia tree).
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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. http://en.wikipedia.org/wiki/Gonio