Kastro
At the Northern point of the island lie the ruins of Kastro, the fortress which the medieval town once nestled. Its inhabitants lived from around 1300-1829.

The Kastro, which commands panoramic views, was built on a gigantic rock springing from the sea. It is more of a natural fortress than a man made one as three of its four sides overlook the sea and are surrounded by walls. However the inhabitants seem to have relied more on the excellent protection from enemy pirates cruising the waters than on the steep rock faces or the walls themselves.

The town was comprised of around 300 tiny houses and 30 churches, of which only 3 have been restored. The Kastro was abandoned in 1829 when the Venetians occupied Skiathos and protected the local people from the pirates, this allowed them to move and build the town as it is today.

Evangaiistria Monastery (The Annunciation Of The Virgin Mary)
The Evangaiistria Monastery was built into the beautiful landscape above Skiathos town. It was constructed in the 18th century by rebel monks from Mount Athos on the Sreek mainland. The Monastery is a large and imposing building erected so that it is almost invisible from any direction, an important factor when pirates are abundant in the surrounding waters.

During the revolution against the Turks, which started in 1821, the heroes of the Sreek revolution used the monastery as a secret meeting place. It was also said that the first Sreek flag, as it flies today, was first sewn in the Evangaiistria Monastery in 1807.

The Evangaiistria Monastery is the only "active" monastery on the island today. However, the number of monks residing here has significantly decreased from 65 to the remaining two remaining there today.