This is a square (10X10 mm.), five-storey, 20-meter high tower made of local slate and marble. It is the perfect example of a fortified tower of the Hellenistic period. Also, it is one of the highest surviving ancient buildings. It functioned as a defensive fortification for the surrounding rural area and when the monastery of Agia Marina was founded, the tower was included in the precinct for defensive reasons. On September 8th, 1858 the tower collapsed after an earthquake and some of the material was used for the repair of neighboring buildings.

In Karthaia you will see the remains of an ancient city that dates back to the Geometric  - early Christian period. Near Karthea you will also find the Doric Temple of Pythian Apollo (approximately 530 BC), which was the main place of worship of the city. In the area there is also the Doric temple of Athena (approximately 500 BC) with her statue in it. Traces of smaller buildings of the ancient city have also been found in the same region. The place is open at all times and the admission is free.

The Lighthouse of St. Nicholas is located opposite the port of Korrisia, on the tip of the peninsula. It is built on the ruins of the sacred temple of Poseidon by the French Company of Lighthouses and it is the first lighthouse in the Cyclades (1831) and the second in Greece. It has been declared a monument by the Ministry of Culture and Tourism as it is a"particularly remarkable architectural construction and a representative sample of lighthouses". You can reach it through a footpath.

The Monastery of Panagia Kastriani, who is also the patron of the island, is within a walking distance from Otzias Beach, on the northeast of the island. The monastery is built on the location that the image of the Virgin was found by shepherds in 1700. Initially, a small chapel was built there (1708) and the monastery as we know it today was built in 1910 in order to accommodate the crowds of people who gathered to pray. The monastery cells function as hostels, and local delicacies are served in the dining room.

Makronissos Island is situated between Kea and Lavrion. The island today is uninhabited except for a few shepherds who live there. Legend says that Paris, the man who caused the Trojan war, hid Helen in a cave on the north side of the island. This is why the island is also known as "Isle of Helena" .

The church of St. Symeon is located at the top of the hill on the southeast side of Kea. It is built on the place where the sanctuary of Aphrodite used to be and the entrance is made of marble from the ancient temple. The church offers a panoramic view of the Aegean sea that will take your breath away.

The feast of St. Symeon takes place every September 1st and is one of the largest celebrations in Kea.

This used to be an industrial area as it was the harbor-station for ships carrying coal in Greece. Today the place has decayed but back in the days it was a powerful and financially important part of the island. 

This small picturesque fishing village near the harbor of Kea has developed a lot in recent years. Dozens of yachts and sailboats are anchored in the sheltered bay and the dock is full of fish taverns, cafeterias, bars, shops and galleries.

Kea has a hiking trails network with a total length of 36 km. The footpaths of the island have been declared a network of "Cultural Interest”. The footpaths will take you through forests of oaks where you can admire the wonderful wildflowers, the handmade stone wells and the whitewashed, picturesque churches. Some of the trails have a historical and archaeological interest because in the past they used to be part of the road network linking the four cities-states.

More information here.

Gialiskari is just 1.5 km from the port of Korissia and it is one of the most popular beaches of Kea. It combines sand with turquoise waters and tamarisk trees.The beach is organized.