It is considered as the most beautiful Norman Cathedral in England and is dedicated to Sts Peter, Paul and Andrew.
A monastic church was founded in Peterborough by King Peada in 655 AD, destroyed by the Danes in 870, rebuilt as part of a Benedictine Abbey and reconsecrated in 972, burned down in an accidental fire in 1116 and re-built in its present form between 1118 and 1238. The porch was added about 1380, the eastern extensions around 1500 and the central tower was re-built in the mid 1300's and again in the 1880's. In 1539 the monastery was closed by Henry VIII, but eighteen months later in 1541, the church became the Cathedral of the new Diocese of Peterborough, with the last abbot as the new bishop, and Peterborough became a city.
The information above was taken from the Peterborough Cathedral website. In it, there is also a link that describes a short history of the Cathedral. Aside from its huge and beautiful structure, both inside and outside, the Cathedral's other claim to fame is that it is where two queens during the Tudor period were buried: Katherine of Aragon (one of the wives of Henry VIII) and Mary Queen of Scots. The latter's grave, however, is now empty as she was re-buried in Westminster in 1612. The Abbey's most valued relic - St Oswald's Arm, disappeared from its chapel about the time of the reformation but the chapel still has its newel staircase or watch-tower where monks kept guard over it day and night.
Nowadays, the Cathedral still follows its centuries old pattern of daily worship. However, the medieval monastic pattern of eight sessions per day has been reduced to morning prayer, daily Eucharist and evensong on most days of the week.
Note: the text of this post are mostly taken from the Peterborough Cathedral website (http://www.peterborough-cathedral.org.uk/).