I absolutely love Oviedo and the rest of Asturias. What friendly people, a very large international student community, close to 'nature' if you like the beach/mountains (think the US Pacific Northwest). Great food and pubs. This isn't your 'typical' Spain but it is gorgeous nonetheless.
The north of Spain is usually forgotten by mass tourism. This "little secret" allows for excellent prices, astonishing sites, beautiful countryside, delicious gastronomy, lot of history etc. Oviedo, a relatively small town with ample walkable streets and avenues, lots of excellent restaurants, cafeterias, bars and other gathering places ...