Cambridgeshire is a historic county of eastern England, bounded by Huntingdonshire and Bedfordshire to the west, Hertfordshire and Essex to the south, Lincolnshire to the north, and Norfolk and Suffolk to the east. Old surveys measured it at about forty miles long and twenty-five broad, with a population clustered into one city, nine market towns and 163 parishes lying chiefly in the diocese of Ely. The county was, and remains, defined above all by the great flat fenland in its north, an area antiquarians described as spreading over some 300,000 acres into neighbouring Norfolk, Suffolk, Huntingdonshire and Lincolnshire, cut through by innumerable drains and channels and forming, together with the surrounding higher ground, a shape likened to a horseshoe.
The Isle of Ely, the raised northern portion of this fen country, was noted for damp, unhealthy air but remarkably rich pasture, its spongy peat soils sustaining large numbers of cattle even where crops would not grow. The drier uplands towards the south-east, by contrast, gave excellent bread-corn and barley, and the poorer, sandier tracts had been improved within living memory by sowing sainfoin, a fodder crop said to have been brought originally from the Holy Land.
Cambridge itself, seat of one of Europe's oldest universities, dominated the county's antiquities: its colleges, chapels and the round church were singled out by eighteenth-century travellers as among the most remarkable buildings in England. Ely's cathedral, rising alone above the fen like a ship at sea, and the ruined abbeys of Denny, Barnwell and Thorney recalled a landscape once thick with religious houses before the Dissolution. Beyond the university city, market towns such as Newmarket on the county's eastern edge and a scatter of great houses including Wimpole gave the shire its enduring character as both an intellectual centre and a working agricultural county.