Maroulas
Excavations at Maroulas uncovered a Mesolithic (9000-8000 B.C.) settlement. Evidence suggests it may have been a resupply station or staging base. Archaeologists unearthed circular dwellings and graves, while finds included a human skeleton and a number of stone tools made from firestone, quartz, and obsidian. The site is the only open-air Mesolithic settlement known in Greece.
Kastro Orias
The Oria kastro (fortifications) is located on the island's northern area, between Sklavo and Yialoudi hills just before reaching of Cape Kefalos.
Wind and Solar Park
The wind-power and solar-energy park is located near the heliport, just outside Hora. Wind-powered generators and solar heat collectors at the park are used to power the island.
Byzantine Museum
A small Byzantine collection is housed in Ai Georgis church at Dryopida and is open daily from 10 a.m. to 2 p.m. and from 7 p.m. to 9 p.m.
Ai Minas Church
The church dominates Dryopida and is worth visiting for its exquisite wood-carved iconostasis and epitaphios (funerary bier used in Holy Week services) and a bishop's throne that offers a fine example of folk art.
Ayios Savvas Church
The church is located in Hora. A carving over the threshold establishes the year of its founding as 1613.
Folklore Museum
Located in Dryopida, the museum features a small but interesting collection of antique tools and other implements that offer a flavor of day to day life in earlier centuries alongside a collection of traditional costumes.
Panayia Kanala Monastery
Dedicated to Panayia Kanala (Our Lady of Kanala), the island's patron, the monastery is built into the rocks near the coastal settlement at Kanala.
Panayia tou Nikous Monastery
Located about 800 meters from Hora, the monastic community likely takes its name from the Byzantine-era Panayia tis Nikopoiou, that is, Our Lady Who Brings Victory (nike).
Katafyki Cave
One of the Greece's largest caves, Katafyki features stalactite and stalagmite formations. It's located at Dryopida.
Thermal Baths
The Kithnos Spa was built at Loutra in 1857. It's open daily from June through October and has two medicinal springs where visitors can take treatment. The baths of King Othon (Otto) and Queen Amalia, the first monarchs of the Modern Greek State, are exhibited here.