Just outside the borders of Green Park is Spencer House, completed in the Palladian style in 1766 for the first Earl Spencer, an ancestor of the late Princess Diana. The Spencers moved out in 1927 and their grand family home was used as an office, until Lord Rothschild stepped in and returned it to its former glory in 1987 with an £18-million restoration. Visits to the eight lavishly furnished state rooms designed by John Vardy and James ‘Athenian’ Stuart are by guided tour only.
The 18th-century gardens are open only between 2pm and 5pm on a couple of Sundays in summer; consult the 'What's On' section of the website for details.