The Platamon Castle (Greek: το κάστρο του Πλαταμώνα), an important part of the history of Pieria, is a Crusader castle (built between 1204 and 1222) in northern Greece (Macedonia) and is located southeast of Mount Olympus, in a strategic position which controls the exit of the Tempe valley, through which passes the main road connecting Macedonia with Thessaly and southern Greece. The tower (donjon), which overlooks the highway, is an imposing medieval fortress.

Important discoveries are the board of Hellenistic wall, that confirm the suggestion that on this position was the ancient Greek city Herakleion and the gate in the wall of the donjon. The core of the city Herakleion remains to be found, but it is posited that it is located on the northwest side of the castle's hill due to shells and coins found during recent excavations.

A footpath leads from the parking lot to the gate of the castle. It is open every day between 08:30 and 15:00. What we call Platamon today included the city of Platamon and the actual castle. The extensive area is designed as a polygon and had irregular towers at irregular intervals. At the foot of the hill, to the left and right of the land, which extends into the sea, are two smaller towers. Only the main tower, the donjon, which is surrounded by its own wall, is located in the western part of the complex. Unfortunately, it is not open to visitors. Here, in fighting, was the last retreat for the inhabitants. For strategic reasons, there is only a relatively narrow gate that can be defended well. Many of the basics of churches, houses, a smithy, pottery and other buildings testify to the life of the past. Partially well-preserved cannons served in the later Middle Ages, the defense of pirates and the general defense of the fortress. To ensure the water supply during a longer lasting siege, there are several cisterns on the site.

The walls have a height of 7.50 to 9.50 m and have a thickness between 1.20 and 2 meters. In the course of the centuries, they have been continually increased, and the individual sections of the building can still be seen today. Except for the destroyed upper part of the defense route in the east, they are well preserved. The wall is accessible in several places for visitors and invites you to enjoy the fantastic view of the surroundings.

Originally the castle complex was surrounded by another, lower wall. It formed the first line of defense in an emergency. The only intact building is the small church Agia Paraskevi. It is richly decorated and offers space for around 30 believers.

Paradoxically, the construction of a railway tunnel through the hill a few years ago has, from the point of view of archaeologists, used the facility more than harmed. During the construction, further ground plans of buildings were discovered which are assigned to the historic city of Herakleion.

Today, the acropolis serves as one of the Olympus Festival venues. In the open air, with good acoustics, theatrical performances and concerts take place here.