Portman Square is a square in London, part of the Portman Estate. It is located at the western end of Wigmore Street, which connects it to Cavendish Square to its east. It is served by London bus route 274
It was built between 1674 and 1684 on land belonging to Henry William Portman. It included residences of Sir Brook Bridges, 3rd Baronet, Henry Pelham-Clinton, 4th Duke of Newcastle-under-Lyne, George Keppel, 6th Earl of Albemarle, Sir Charles Asgill, 1st Baronet and William Henry Percy.
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