Sherlock Holmes' Study – 221b Baker Street, Marylebone, London, England

221b Baker Street is the London address of the fictional detective Sherlock Holmes, created by author Sir Arthur Conan Doyle. When the "Sherlock Holmes" stories were first published, street numbers in Baker Street did not go as high as 221, which was presumably why Conan Doyle chose a higher street number for the location of his hero, to prevent any person’s actual residence from being affected. When street numbers were reallocated in the 1930s, the block of odd numbers from 215 to 229 was assigned to an Art Deco building known as Abbey House, constructed in 1932 for the Abbey Road Building Society, which the society and its successor (which subsequently became Abbey National plc) occupied until 2002. Almost immediately, the building society started receiving correspondence from Sherlock Holmes fans all over the world, in such volumes that it appointed a permanent "secretary to Sherlock Holmes" to deal with it.