Amsterdam's main attractions include, the Royal Palace of Amsterdam, the Van Gogh Museum, Hermitage Amsterdam, and the Amsterdam Museum. The city is also well known as the cultural capital of the Netherlands. Primarily known for its artistic heritage, elaborate canal system and narrow houses with gabled façades; well-preserved legacies of the city's 17th-century Golden Age. The KLM hub and Amsterdam's main airport, Schiphol, give quick and convenient transport to the heart of the city. Amsterdam is considered an alpha world city by the Globalization and World Cities study group, and the city is considered one of the most multicultural cities in the world, with at least 177 nationalities represented.