Andalusia, Aragon, Catalonia, Galicia, Leon, and Castile are all Spanish regions. Andalusia is the most populous region in Spain, located in the south of the country. Aragon is located in the northeast of Spain and is known for its historical sites. Catalonia is located in the northeast of Spain and is home to Barcelona. Galicia is located in the northwest of Spain and is known for its green landscapes. Leon is located in the northwest of Spain and is known for its medieval architecture. Castile is located in the center of Spain and is known for its cultural heritage.