46, Park Street, Mayfair, England

The lease on 46, Park Street in Mayfair was acquired by Lionel de Rothschild (1882-1942) shortly after his marriage to Marie-Louise Beer (1892-1975) in 1912. The house was built in 1911–1912 to designs by Detmar Blow and his French partner Fernand Billerey.

The house formed a block of six large houses (two properties facing onto Upper Grosvenor Street). The façade is a fine piece of Beaux-Arts classicism, fifteen bays wide and four storeys high. The composition is tied together by a prominent modillion cornice at attic level, the balustrades below the first-floor windows and along the parapet, and the French-style channelling of the Portland stone masonry. The centrepiece is an attached Ionic portico with fluted columns stretched over three storeys. The interiors were finely detailed and many contained imported marble chimneypieces.

At No. 46 Park Street minor alterations were made for Lionel by W. H. Romaine-Walker in 1913. Edmund de Rothschild (1916-2009) was born at 46 Park Street.