I'm in second year now and stayed at Castle Leazes in first year. The corridors are single sex but that doesn't tend to be much of a problem because there's plenty of girls around too if you want to be near girls. Castle Leazes gets a bit of a rep for being a "rah haven" and, from my experience, this is kind of justified: in my corridor the majority of people had went to private schools and in the accommodation as a whole there was a lot of public school cliqueness, like all the Harrow boys stuck together and all the Winchester boys... And in some cases I was looked down on for not having went to a public school but that wasn't too common. One time a guy from Fettes (public school in Edinburgh) asked which school I went to and when he heard "grammar school" then he was like: "Oh, so not a fee paying school then? Ah... okay", haha. But then we became best mates the next term! I loved my time at Castle Leazes and wouldn't have stayed anywhere else, it was awesome! I would totally recommend it to anyone but if I could do it again I probably would go for Castle Court just because the rooms are a little nicer. If you have any questions then feel free to ask me.