The capital Kythnos Town is in the mountainous center of Kythnos. It's 8 km north of the port Merichas. It has no hotels and only a few rooms to let.
The narrow, picturesque alley-like pavements of Kythnos Town are covered with painted designs of fish, flowers, mermaids and spiral patterns. It is a real Greek village with a character all its own. There are several churches among which the most notable are Aghias Savvas (1613) and Aghia Triada with its beautiful wood-carved screen, single-aisle basilica. Other churches claim icons made by Cretan-Venetian master Skordilis, including The Prodromos or Scout of St. John Church.
Just outside Kythos Town is the solar park and modern power-generating windmills. The steady wind keeps the windmills spinning.
The two iron-saturated springs at Loutra, Kakavos and Aghia Anargyri are the most important spas in the Cyclades. Both are used for bathing and as a cure for gout, eczema, rheumatism and something known by the antiquated term 'woman's problems'. Loutra is a small resort with some holiday villas, a few tavernas and rooms to let as well as the Xenia Hotel which houses the Hydrotherapy Center and boasts ancient carved marble baths from which steaming water bubble forth.
Over the headland are two small bays hiding the small pebbled Aghia Irini Beach and Schinari which gets the brunt of the north wind. The oldest Mesolitic settlement found in the Cyclades is on the promontory just to the north.
At Kythnos northern tip, an hour's walk from Loutra is the deserted medieval Castle Kastro Katakefalos. This medieval ciadel was abandoned in the 17th Century.