Welcome to Greece! Tourism in Greece has been a key element of the economic activity in the country, and is one of the country's most important sectors. Greece has been a major tourist destination and attraction in Europe since the 1970s for its rich culture and history, which is reflected in large part by its 18 UNESCO World Heritage Sites, among the most in Europe and the world as well as for its long coastline, many islands, and beaches. The Egremnoi sand beach in the Greek island of Lefkada, noted for its blue crystal waters, is a popular tourist destination. Greece attracted as much as 33 million visitors in 2018, up from 24 million in 2015, making Greece one of the most visited countries in Europe and the world, and contributing around 25% to the nation's Gross Domestic Product. Its capital city Athens, as well as Santorini, Mykonos, Rhodes, Corfu, Crete and Chalkidice are some of the country's major tourist destinations. In recent years, Greece has also promoted religious tourism and pilgrimages to regions with a significant historical religious presence, such as the Christian monasteries in Meteora and Mount Athos, in cooperation with other countries. Greece also is one of Europe's most popular LGBT tourist destinations, particularly its largest cities Athens and Thessaloniki and some of its islands such as Lesbos, Skiathos and Mykonos. The latter is a well-known Gay-friendly destination with many establishments catering for the LGBT community. Greece has a Mediterranean climate along its coasts and islands. Once inland, many areas and cities experience a continental climate.