It is named after Margaret Bentinck, Duchess of Portland.
The Anglo-Dutch merchant banker, author, philosopher and art collector Thomas Hope had an Egyptian-influenced house built at no.
[1] The building has been Grade II listed since 1954.
[2] The Egyptian Room in his house was the inspiration for the Egyptian Hall in Piccadilly, an exhibition hall built in the ancient Egyptian style in 1812, and demolished in 1905.
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