Valencia is the capital of the autonomous community of Valencia and the third-largest city in Spain after Madrid and Barcelona. The port city of Valencia lies on Spain’s southeastern coast, where the Turia River meets the Mediterranean Sea. It’s known for its City of Arts and Sciences, with futuristic structures including a planetarium, an oceanarium and an interactive museum. Valencia also has several beaches, including some within nearby Albufera Park, a wetlands reserve with a lake and walking trails. The city is ranked at Beta-global city in the Globalization and World Cities Research Network. Its historic center is one of the largest in Spain, this heritage of ancient monuments, views and cultural attractions makes Valencia one of the country's most popular tourist destinations.