Aspley House, if home to the Duke of Wellington, who is most famous for beating Napoleon at the battle of Waterloo in 1815 but he was also Prime Minister twice.The place was known as Number 1, London in the Duke's time. It is now a Military Museum.
The house was given back to the nation, but the family still use the private rooms. It is the last surviving townhouse in London that is open to the public but also the only EH property that the original owner's family is still alive.
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American to Britain