In southwest London’s Royal Bushy Park, a Cold War-era torpedo testing site has been reimagined as a striking six-bedroom home. Known as Rotunda, the singular residence has hit the market for £7.5 million (about $10.1 million) and offers more than 10,000 square feet of contemporary living space wrapped around a circular walled garden with a sunken courtyard at its center.
Originally built by the Admiralty in the 1950s as a 150-foot-diameter water tank used for underwater…