It feels like a small town in the middle, that's the main difference. If you leave the centre (the uni area, basically) it actually goes on for ages and feels a lot more like an actual city. It is smaller than Oxford, but not by as much as it might feel like on first impressions. 120,000 compared to 150,000 according to wiki.
The centre really can feel like a rural market town but with a few more shops, people, and fancy buildings though.