Sherlock Holmes Museum

The Sherlock Holmes Museum is a privately run museum in London, England, dedicated to the famous fictional detective Sherlock Holmes. It opened in 1990 and is situated in Baker Street, bearing the number 221B by permission of the City of Westminster, although it lies between numbers 237 and 241, near the north end of Baker Street in central London close to Regent's Park.

The Georgian town house which the museum occupies as "221B Baker Street" was formerly used as a boarding house from 1860 to 1936, and covers the period of 1881 to 1904 when Sherlock Holmes and Doctor Watson were reported to have resided there as tenants of Mrs Hudson. The museum is run by the Sherlock Holmes Society of England, a non-profit organization.

The address 221B was the subject of a protracted dispute between the museum and the nearby Abbey National building. Since the 1930s, the Royal Mail had been delivering mail addressed to Sherlock Holmes to the Abbey National Bank, and they had employed a special secretary to deal with such correspondence. The museum went through several appeals for such mail to be delivered to it, on the grounds that it was the most appropriate organization to respond to the mail, rather than the bank whose primary business was to lend money out on interest. Although these initiatives were all unsuccessful, the issue was finally resolved in 2002 when the Abbey National vacated its headquarters after seventy years, and the mail is currently delivered to the museum.