lololol. cambridge is the worst place for haircuts, in the world probably.
i don't think there are any west of the river, so...
the closest i think is Mr Politos. i think i got cut by Mr Polito himself when i went there, and with his first snip he cut my entire fringe off, which i did not ask for. i went a second time, actually, and a fat woman cut my hair. not great. £11, i think.
then there's that place that has the boards outside, and has the student offer thing. most people seem to go there, and they all come back having the exact same haircut. £11 again i think, and awful.
the best (and final) place i've been is Parkers, on Regent Street. it looks slightly more funky than the other places, and the lady cutting my hair was quite nice. her hands smelled of cigarettes too, which i kind of like. £11 again.
if you remotely care about your hair, i'd recommend getting it cut outside of cambridge, or if you can afford it, go to Toni & Guy.