Greece, also known as Hellas, and officially the Hellenic Republic, is a country located in Southeast Europe. Its population is approximately 11,3 million.  Athens is its largest and capital city, followed by Thessaloniki. Greece is located on the southern end of the Balkan Peninsula; it lies at the meeting point of three continents – Europe, Asia and Africa. Greece borders to the North on Bulgaria and the Republic of North Macedonia, to the Northwest on Albania, to the Northeast on Turkey; to the West it is washed by the Ionian Sea; to the South by the Mediterranean Sea and to the East by the Aegean Sea. The total area of Greece is 131,957 km2 and consists of three main geographic areas: a peninsular mainland (that extends from the region of Central Greece on the South to the region of Thrace on the North) being the biggest geographic feature of the country, the Peloponnese peninsula that is separated from the mainland by the canal of the Corinth Isthmus, and around 6.000 islands and islets, scattered in the Aegean and Ionian Sea, most of them grouped in clusters, that constitute the unique Greek archipelago. Eighty percent of the country consists of mountains or hills, making Greece one of the most mountainous countries of Europe; furthermore, it has 16.000 km of coastline of which 7500 are found around the thousands islands of the Greek archipelago. The country is a Parliamentary Republic. The official language is Greek. Greece is a Member-State of the European Union and uses its uniform currency – the Euro. Education in Greece is enshrined in Article 16 of the Greek Constitution, which sets out that: Education constitutes a basic mission for the State and shall aim at the moral, intellectual, professional and physical training of Greeks, the development of national and religious consciousness and at their formation as free and responsible citizens. The same article also guarantees that "Art and science, research and teaching shall be free and their development and promotion shall be an obligation of the State". The Greek education system is under the central responsibility and supervision of the Ministry of Education and Religious Affairs. The Greek educational system is mainly divided into three levels: primary, secondary, and tertiary, with an additional post-secondary level providing mainly vocational training.