This grand neoclassical mansion, located at the northern end of Hampstead Heath, boasts a magnificent landscape of gardens rolling down to a tranquil pond. In the 1760s, it was extensively remodelled and later, in 1927, was saved from destruction by Edward Cecil Guinness, 1st Earl of Iveagh, who gifted it and its exquisite collection of artwork, including masterpieces by Rembrandt, Constable, Turner, Gainsborough and Vermeer, to the nation.