I had a bike stolen from Leeds University (the bike locks outside the union building near the gate, around 11pm at night... bad time to leave a bike, but still). Also one from Leeds city centre (bike locks next to the Light, opposite the cashpoint in the street between the cinema and Hard Rock Cafe). Again, at night. I've learned my lesson and don't leave bikes anywhere at night, with the rare exception of the train station (have to have a ticket to get in there and there's always loads of bikes locked up, no matter what the hour). I'd just say carry a couple of locks (D lock and a cable/chain one, ideally) if your bike's half decent.
Leeds as a city is great for it though, bike lanes on most roads. I commute 10 miles a day and it's quicker than the bus.