Although trains did stop within the town, Slough's first railway station proper didn't open until June 1, 1840, after the repeal of a strange clause in the Great Western Railway Act. The clause stipulated that there be no station built within three miles of Eton College. According to Chambers's Edinburgh Journal, "the masters were afraid that the temptation to 'run up to town' rather often would be too strong to be resisted by their pupils; for the distance is only eighteen miles".
This piece of trivia came up in the first episode of QI's Series E, where it was implied the masters didn't want their charges within easy traveling distance of London prostitutes.