town of Heracleia. To the north the ancient Pydna is located. Here, in 168 BC, the decisive battle between the Macedonians and the Romans took place. Between Pydna and Mount Olympus are a fortified bishop's seat from the Byzantine period called Louloudies and the Macedonian Tombs of Katerini and Korinos. Christian monuments In the Olympus region, there are also several Christian monuments, among them the highest-elevation chapel of Orthodox Christianity, dedicated to Prophet Elias, in Greek tradition associated with mountaintops, on the summit of the same name (Προφήτης Ηλίας Profitis Ilias), at 2,803 m. It was built in the 16th century by Saint Dionysios of Olympus, who also founded the most significant monastery in the region. The Old Monastery of Dionysios (elevation 820 m) lies in Enipeas' gorge and is accessible by car from Litochoro. It was looted and burned by the Ottomans and in 1943 it was destroyed by the German invaders, who suspected it was a guerrilla den. Nowadays it has been partially restored and operates as a dependency of the New Monastery of Dionysios, that is outside Litochoro. On Olympus's southern foot, in a dominant position (820 m) in Ziliana gorge, there is the Kanalon Monastery, 8 km away from Karya. It was founded in 1055 by the monks Damianos and Joakim and since 2001 it has been restored and operates as a convent. Further west, in the edge of Mavratza stream, at 1,020 m, there is the Agia Triada Sparmou Monastery, that flourished in the early 18th century, possessed great property and assisted to establish the famous Tsaritsani' school. It was abandoned in 1932, but in 2000 it was completely renovated and reopened as a male monastery, affiliated to Elassona's diocese. Climbing expeditions Archaeological evidence suggests that Mount Olympus was regularly visited in religious pilgrimages through antiquity and the early Middle Ages. For instance, ancient Greek pottery, coins, and evidence of sacrificial ashes estimated to be from 400 B.C. have been found on the summit. Plutarch, writing during the Roman Empire, reported that writings and sacrificial ashes left by priests and religious pilgrims on the summit of the mountains of Mount Kyllini and Mount Olympus could be found intact several years later, neither being washed away by rains or scattered by winds. Plutarch cited this as evidence that the highest mountains on earth were above the clouds and winds. Augustine of Hippo, writing in the early