Burlington House is a building on Piccadilly in London. It was originally a private Palladian mansion, and was expanded in the mid-19th century after being purchased by the British government. The main building is at the northern end of the courtyard and houses the Royal Academy, while five learned societies occupy the two wings on the east and west sides of the courtyard and the Piccadilly wing at the southern end. These societies, collectively known as the Courtyard Societies are: