From the settlement of Kelia, one should visit the nearby caves. Among them, one is of significant historic value, and it is the most important site in the area. It is said that in the first centuries AD, it served as a hermitage, while one can still see remarkable murals on the rocks.
The Venetian Fortress of Halki is situated above Horio, the deserted former capital of the island. The Fortress is built near, the ruins of the ancient city, overlooking the beautiful Halki. Inside the Fortress, one can admire the beautiful chapel of Agios Nikolaos with the remarkable frescoes.
The ruins of the Acropole of Horio and the ancient town of Halki are not only among the most important sights of Horio, the island's former capital, but of the island as a whole. A Venetian castle stands right over the present town of Horio. Inside, there is an old chapel dedicated to St Nicholas. From that spot, the view to the sea is breathtaking.
The church of Agios Nikolaos at Halki was built in 1861 on the ruins of a Venetian fortress. From the outside one's attention is caught by the magnificent bell tower. Inside one can still admire significant post-Byzantine paintings and a wonderful wood-carved screen.
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