Mount Olympus (/oʊˈlɪmpəs, əˈlɪm-/,[5] Greek: Όλυμπος, romanized: Ólympos, IPA: [ˈoli(m)bos]) is an extensive massif near the Thermaic Gulf of the Aegean Sea, located on the border between Thessaly and Macedonia, between the regional units of Larissa and Pieria, about 80 km (50 mi) southwest from Thessaloniki.

The shape of Olympus was formed by rain and wind, which produced an isolated tower almost 3,000 metres (9,800 ft) above the sea, which is only 18 kilometres (11 mi) away from Litochoro.

The villages Petra, Vrontou and Dion lie to the northeast, while on the eastern side there is the town of Litochoro, where Enipeas bisects the massif of Olympus.

With the temperature rise that followed, the ice melted and the streams that were created swept away large quantities of crushed rock in the lowest places, forming the alluvial fans, that spread out all over the region from the foothills of the mountain to the sea.

On the southern foothills the great gorge of Ziliana, 13 km long, consists of a natural limit that separates the mountain from Lower Olympus.

[22] One theory suggests that it is compounded of ou lyma (οὐ λύμα) and pous (πούς), meaning "pure foot", conforming to Hesiod's description of the earth as a sort of footstool for heaven up from which rise the "Blessed Gods".

[25] In Homeric Greek (Odyssey 6.42), the variant Οὔλυμπος Oulumpos occurs, conceived of as the seat of the gods (and not identified with any specific peak).

[28] This was conceived of as a lofty mountaintop, and in all regions settled by Greek tribes, the highest local elevation tended to be so named; among the numerous peaks called Olumpos in antiquity are mountains in Mysia, Laconia, Lycia, Cyprus, Attica, Euboea, Ionia and Lesbos, and others.

In Pieria, at Olympus's northern foot, the mythological tradition had placed the nine Muses, patrons of the Fine Arts, daughters of Zeus and the Titaness Mnemosyne.

In the early 20th century, even for some time after the liberation from the Ottoman Empire (1912), robbers were active in the region – the best known of them the notorious Giagoulas (el), while during the German invasion in 1941 the Hellenic Army fought significant battles along with units of New Zealanders and Australians.

[32] By the sea, in a strategic position, at Macedonia's gates is located Platamon Castle, built between 7th and 10th century AD in the ancient town of Heracleia.

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.

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.

Archaeological evidence suggests that Mount Olympus was regularly visited in religious pilgrimages through antiquity and the early Middle Ages.

Augustine of Hippo, writing in the early Middle Ages, similarly reported in On Genesis that "on the peak of Mount Olympus, which is said to rise above the area of this humid air, we are told, certain letters are regularly made in the dust and are a year later found whole and unmarred by those who climb that mountain for their solemn memorials.

"[34] The third highest peak of Mount Olympus, called Agios Antonios (Άγιος Αντώνιος "Saint Anthony", 40°04′04″N 22°21′04″E / 40.0677°N 22.3511°E / 40.0677; 22.3511, 2,817 m), is known to have been the site of a sanctuary of Zeus in antiquity based on archaeological finds discovered in 1961.

The Swiss Frédéric Boissonnas and Daniel Baud-Bovy, aided by a hunter of wild goats from Litochoro, Christos Kakkalos, were the first to reach Greece's highest peak.

In 1928, the painter Vasilis Ithakisios climbed Olympus together with Kakkalos, reaching a cave that he named Shelter of the Muses, and he spent many summers painting views of the mountain.

Olympus was later photographed and mapped in detail by others, and a series of successful climbs and winter ascents of the steepest summits in difficult weather conditions took place.

Climbing Mount Olympus is a non-technical hike, except for the final section from the Skala summit to the Mytikas peak, which is a YDS class 3 rock scramble and due to high exposure to heights, requires resistance to acrophobia.

In the lower locations (Litochoro and the foothills) the climate is typically Mediterranean, i.e. hot and dry in the summer, but humid and cold in the winter.

[12] The coastal northeast slopes of Olympus receive more rain than the continental northwest, so, as a result, there is a clear difference in vegetation, being more abundant in the first of them.

For this Olympus's alpine region, recordings have been made in the 1960s in the highest-elevation weather station in Greece, that was established on the summit of Aghios Antonios (2,815 m), providing a number of interesting data for the mountain's climate.

[41][42] An important book about the plants and flowers, from the beach of the Aegean Sea up to the upper regions of Mount Olympus, was written in 1980 by the Swedish botanist Arne Strid.

In Olympus there are generally four sequential flora zones, but due to the complex topography and variety of microclimates, these do not form an obvious clear sequence with elevation.

While in the neighboring mountains Pierians and Ossa it creates an extended vegetation zone, in Olympus it is restricted to small clusters, appearing as islets, mainly in more humid locations and the best soils.

[14] One can see there elm, cherry plum, European yew, hazel, holly, Cornus mas, manna ash, maple and a considerable variety of herbaceous plants.

The vegetation growing there is adapted to specific local conditions and represented by typical shrubs, graminaceous, chasmophytes etc., while the flora includes many endemic species of the Balkans.

[41] Greece's highest mountain, dwelling of the Twelve Gods of antiquity, has been the first region in the country to be applied specific protective rules, by its declaration as a National Park in 1938.

It informs their visitors about geology, archaeological sites, mythology, monasteries, plants, animals and other subjects affecting Mount Olympus.