POTIDÉE CANAL

This 1,250 m long, 45 m wide artificial canal (Διώρυγα της Ποτίδαιας/Dioryga tis Potidaias) separates the Kassandra peninsula from the rest of Chalkidiki to the north. It is bordered to the south by the remains of fortifications that protected the ancient city of Potidaea, now occupied by Nea Potidea. Shallow (8 m), the canal allows fishing boats and pleasure craft to pass from the Tornonean Gulf in the east to the Thermaic Gulf in the west, avoiding a 60 nautical mile (over 110 km) detour via Cape Kanastreo in the south of the peninsula. Dug at the narrowest and lowest point of the Pallene Isthmus, the canal took its present form in 1937. Since 1970, it has been spanned by a new bridge for cars, cyclists and pedestrians, where freeway 24 from Thessaloniki ends. But its history goes back much further. Also known as the "Kassandra Canal", it was the brainchild of the Macedonian king Cassander, founder of Cassandra (now Potidea) and Thessaloniki. He began digging the site around 315 BC. However, it was the Romans who completed the excavation in the ^1st century BC.

Justinian Wall. Too narrow and frequently silted up, the canal was widened in 1407, then again between 1935 and 1937. Today, with a small port at each end, the canal is not particularly suitable for strolling: despite a development project announced for 2022, its tree-lined banks are still flanked on both sides by a road with no real sidewalk. However, at bridge level, to the south and away from the road, a 70 m section of the "Justinian wall" with three towers remains. Also known as the "transverse wall of Cassandra", this stone and brick fortification originally extended along the entire length of the canal, with walls 2-3 m thick and 19 towers 8-10 m high. It was created during the reign of Cassander, then modified by the Romans, Byzantines and Venetians until 1424, notably during the reign of Justinian, after a Hun raid in 540. The defensive system was extended at the eastern mouth of the canal by a fortified islet (off the northern harbor), where the base of a square tower is still visible. The wall was damaged during the anti-Ottoman uprising of 1821, then largely destroyed in the 1920s-1930s, when Greek refugees from Eastern Thrace settled here and the canal was widened. The materials were used in the construction of the large Agios Georgios church, completed in 1925.