On the Iberian Peninsula, Spain consists of 17 autonomous regions with diverse cultures and geographies. Spain's capital city, Madrid, is home to the Royal Palace and the Prado museum, which exhibits the works of European masters. In Segovia, you can visit a medieval castle called the Alcázar and a Roman aqueduct that is still intact. It is Catalonia's capital, Barcelona, that is known for Antoni Gaud's whimsical modernist landmarks like the Sagrada Família church.