Itanos was particularly powerful community during the Greek era and it was flourishing by the seventh century BC. Itanos was continuously at war with its neighbours Praisos, and later Hierapytna.
In the 8th century AD Itanos was destroyed in an earthquake but the inhabitants stayed and rebuilt the town. Only in the 15th century after attacks by pirates the town was finally destroyed and deserted. Because the west of Crete slowly elevates upwards and the east odf the island is slowly sinking (6 to 9 meters in the last 2000 years, mainly caused by earthquakes) parts of the harbour of Itanos have now sunk into the sea.
Herodotos was the first Greek historian who mentioned Itanos. The archeological site of Itanos is open to the public. It is possible to see the ruins of houses, city walls and Christian churches. Many Greek inscriptions were found in situ; the most famous one, kept now in the monastery of Toplou, relates a decision by the Roman Senate about Itanos' conflicts and territorial disputes with the neighbor cities Praisos and Hierapytna.
The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.