The Efpalineio tunnel is a tunnel of 1036m near Pythagoreio of Samos, which was constructed in the 6th century in order to work as an aqueduct.
Its special characteristic is that it was opened simultaneously by both sides of the mountain, this tunnel was double-edged as Hrodotos called it, because of what it was known for.
The two tunnels met almost in the middle with a remarkable accuracy, a very important achievement for those times. A part of the tunnel is open to visitors today.

3km out of Karlovasi, in the area "potami", you will find the famous waterfalls of Samos.
The waterfalls have an exquisite natural beauty and create two small lakes, ideal for the bold who want to swim in their cold water. To admire the waterfalls up close you will have to drive to Potami and from there walk an extra 1,5km reaching the church of Metamorfosis, the oldest church of the island which was built in the 11th century. That point is the exact half way to the waterfalls. From then on you will continue by climbing 50-60 wooden paths to get to the first waterfall. If you want to get to the large waterfall you will have to swim about 50m, because at that point the water gets deep and you can't continue on foot.
Make sure you have a swim suit with you and dive into the waterfalls, which reach 5m in height. This experience will be unforgettable.

The temple of Hera is located 3km west of Pythagoreio, near the south coast of the island and it's the most important temple of Samos, and one of the most important in Greece.
The temple of Hera is dedicated to the goddess Hera, the wife of Zeus, the king of the 12 gods of Mount Olympus. In ancient times this temple was declared as a sacred place, and continued to be tll Roman times.

Northwest of Pythagoreio, in a near distance, in a large cave a small chapel is located which is dedicated to the Virgin Mary. In the chapel there is a marbel icon of the Virgin Mary, which is so old that it is difficult to make out the figure.
Next to the church you will find Holly Water. Outside the cave there is a church dedicated to Saint George and a few chambers. The church of Siliani belongs to the Monastery of Hazoviotissa of Amorgo.
Spiliani is also known as Kaliarmenissa to the locals. Access to the Monastery is very easy with a private or rental vehicle from Pythagoreio, even by taxi.