Fortunately for Eisenhower, the Luftwaffe seem to have overlooked this one

From The Road to Little Dribbling: Adventures of an American in Britain by Bill Bryson. Page 60.

I had never been on Putney Heath or Wimbledon Common – they run seamlessly together – and they were splendid. They were not at all like the manicured parks I had grown used to in London, but were untended and rather wild, and all the more agreeable for that. I walked for some time over heath and through woods, never very sure where I was despite having an Ordnance Survey map. The further I walked, the more isolated things felt.

At one point it occurred to me that I hadn’t seen anybody for about half an hour, couldn’t hear traffic, had no idea where I would be when I next saw civilization. I had set off with the vague thought of walking past the site of Dwight D. Eisenhower’s home during the Second World War, which I had by chance recently discovered lay more or less along the route I was taking today. I had read at the library about Eisenhower’s domestic arrangements during the war. He could have had a stately home like Syon House or Cliveden, but instead he chose to live alone without servants in a simple dwelling called Telegraph Cottage on the edge of Wimbledon Common. The house was up a long driveway, the entrance guarded by a single soldier standing beside a pole barrier. That was all the security the Supreme Allied Commander enjoyed. German assassins could have parachuted on to Wimbledon Common, entered Eisenhower’s property from the rear and killed him in his bed. I think that’s rather wonderful – not that Germans could have done that, but that they didn’t.

Although the Germans missed their chance to assassinate Eisenhower, they might easily have bombed him. Unbeknownst to Eisenhower or evidently anyone else on the Allied side, civil defence forces had erected a dummy anti-aircraft gun in a clearing just the other side of a hedge from Eisenhower’s cottage. Dummy guns were put up all around London in an effort to fool German reconnaissance and trick their planes into wasting bombs. Fortunately for Eisenhower, the Luftwaffe seem to have overlooked this one.

Bearing in mind that I was largely lost, you may imagine my delight when I emerged from the common through the grounds of a rugby club, and discovered that I had more or less blundered on to the site of Eisenhower’s cottage, though there is no telling the exact spot any more. Telegraph Cottage burned down some years ago, and today the site is covered with houses, but I had a good stroll around and was satisfied that I had more or less hit my target, which is more than the Germans managed to do, thank goodness.