Greece (Greek: Ελλάδα), officially the Hellenic Republic (Greek: Ελληνική Δημοκρατία Ellīnikī́ Dīmokratía) is a country located in southeastern Europe. According to the 2015 census, Greece's population is approximately 10.9 million. Athens is the nation's capital and largest city, followed by Thessaloniki. Greece is strategically located at the crossroads of Europe, Asia, and Africa. Situated on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, the Republic of Macedonia and Bulgaria to the north and Turkey to the northeast.
Greece consists of nine geographic regions: Macedonia, Central Greece, the Peloponnese, Thessaly, Epirus, the Aegean Islands (including the Dodecanese and Cyclades), Thrace, Crete, and the Ionian Islands. The Aegean Sea lies to the east of the mainland, the Ionian Sea to the west, and the Mediterranean Sea to the south. Greece has the longest coastline on the Mediterranean Basin and the 11th longest coastline in the world at 13,676 km in length, featuring a vast number of islands, of which 227 are inhabited. Eighty percent of Greece is mountainous, with Mount Olympus being the highest peak at 2,918 metres.
Greek history is one of the longest of any country. The country is considered the cradle of Western civilization, having been the birthplace of democracy, Western philosophy, the Olympic Games, Western literature, historiography, political science, major scientific and mathematical principles, and Western drama, including both tragedy and comedy. The Greeks were first unified under Philip of Macedon in the fourth century BC. His son Alexander the Great rapidly conquered much of the ancient world, spreading Greek culture and science from the eastern Mediterranean to the Indus River.
Annexed by Rome in the second century BC, Greece became an integral part of the Roman Empire and its successor, the Byzantine Empire. The first century AD saw the establishment of the Greek Orthodox Church, which shaped the modern Greek identity and transmitted Greek traditions to the wider Orthodox World. Falling under Ottoman dominion in the mid-15th century, the modern nation state of Greece emerged in 1830 following a war of independence. Greece's rich historical legacy is reflected in large part by its 18 UNESCO World Heritage Sites, among the most in Europe and the world. Greece is a democratic and developed country with an advanced high-income economy, a high quality of life and a very high standard of living.