A blue plaque is a permanent sign to commemorate a link between that location and a famous person, event, or former building on the site, which serves as a historical marker -kb with some placed by English Heritage and others by Portsmouth City Council.
There are a number of them in the city – we take a look at where some of them are and who they celebrate:
13. Dame Frances Amelia Yates
Dame Frances Amelia Yates was an historian who focussed on the study of the Renaissance. She was born at 53 Victoria Road North, Southsea, in 1899, as is marked with this blue plaque. She taught at the Warburg Institute of the University of London for many years - one of the world's leading institutes for cultural history studies. She died in 1981. Photo: Google Street View
14. Sir Arthur Conan Doyle
It may not be blue, but Arthur Conan Doyle is celebrated with a brown plaque which can be found on the side of Bush House, Elm Grove, Southsea where first two Sherlock Holmes novels were written. He practiced as a doctor in the city at No. 1 Bush Villas which formerly stood on the site. Photo: Contributed
15. Margaret Rock
A blue plaque for pioneering mathematician Margaret Rock can be found at the old entrance of Portsmouth High School where she once attended. She one of 8,000 female mathematicians who played a pivotal role decoding enemy messages using the Enigma machine. The former student of the private girls’ school was recruited by the Government Code and Cypher School at Bletchley Park in 1940, where she trained and worked alongside mathematicians and professors to break and decode enemy messages. She was considered by Dilwyn Knox, chief cryptographer, to be one of the best in the whole Enigma staff. Margaret received a promotion to the grade of 'linguist', the closest a woman could get to being called a codebreaker and was awarded an MBE in 1945. Her life is commemorated in Kerry Howard's book Dear Codebreaker. She died in 1983. Photo: Tilly Beresford