Salamanca is a city in northwestern Spain that is the capital of the Province of Salamanca in the community of Castile and León. The city lies on several hills by the Tormes River. Its Old City was declared a UNESCO World Heritage Site in 1988. It is one of the most important university cities in Spain and supplies 16% of Spain's market for the teaching of the Spanish language. Salamanca attracts thousands of international students. It is situated approximately 200 kilometres (120 miles) west of the Spanish capital Madrid and 80 km (50 mi) east of the Portuguese border.