Halaesa was an ancient city of Sicily, situated near the north coast of the island. The city was of Siculian origin; in 403 BC the tyrant Archonides of Herbita, having concluded peace with Dionysius I of Syracuse, gave the northern part of his territory to the Sicilians as well as to mercenaries and others who had helped him during the war. He named it Halaesa, to which the epithet Archonidea was frequently added for the purpose of distinction. Others attributed the foundation of the city erroneously to the Carthaginians.
It quickly rose to prosperity through maritime commerce. At the start of the First Punic War it was one of the first of the Sicilian cities to submit to the Romans to whose alliance it was always faithful. It was doubtless to this conduct and to the services that it was able to render to the Romans during their wars in Sicily that it was awarded the status of civitas libera ac immunis which gave it the privilege of retaining its own laws and independence, exempt from all taxation, an advantage enjoyed by only five cities of Sicily. In consequence of this advantageous position it rose rapidly in wealth and prosperity and became one of the most flourishing cities of Sicily.
The city appears to have subsequently declined, and had sunk in the time of Augustus to the condition of an ordinary municipal town, but was still one of the few places on the north coast of Sicily which Strabo deemed worthy of mention.
The site has been partially excavated starting in 2017. The agora and theatre are among the monuments so far been brought to light. Portions of the aqueduct can be seen and fragments of statues, as well as coins and inscriptions, have been frequently discovered on the spot.
References: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.