The story of Cambridge is one of curious conflict: an unrelenting struggle for independence by a squalid fenland settlement, which entirely changed its purpose as, down the centuries, a great University grew in its midst. Yet it was this unwelcome intruder, seen today as an island of ancient glory in a surge of modern expansion, that makes the City of Cambridge known to the world. The coming of the "clerks"; the early hostels and colleges; the problem of the King's Ditch; the limitations of a medieval education, and of learning itself until recent years; the "rod" and its application; the tremendous religious emphasis, and compulsion, that endured until the last century; the dissolution of the religious houses; the Reformation and its martyrs; the threats to the University's very existence; Cambridge and Cromwell, himself a pensioner of Sidney Sussex; the seemingly unending strife between town and gown, and the hazardous office of Mayor; the unending procession of poets and scientists, headed by Milton and Newton, and of great men in every walk of life; the colleges, and their independence, in the modern age of reform, not least in architecture; and even the tidal phenomenon of the undergraduates' hair, once restricted by clerical tonsure; it is in terms of these factors, grave and gay, that the story of Cambridge is told.