Dartmouth House is a grand Georgian townhouse in London’s Mayfair district, renowned for its elegant architecture and cultural significance. 
 
Built around 1755 as two separate residences (numbers 37 and 38 Charles Street), it was acquired by the English-Speaking Union (ESU) in 1926 for £45,000 and officially opened by Prime Minister Stanley Baldwin in 1927. Grade II*-listed since 1987, it retains original features like sweeping marble staircases and Rococo furnishings.
 
Interesting facts...
Banker Edward Baring transformed it in the 1880s into a “rococo opulence” showcase for his Louis XIV furniture, sparing no expense on features like the Belgian marble staircase and a grand mews house—unusually stylish even for Mayfair—much of which survives today.