Drought and extreme heat in England have made it possible to see ancient sites normally hidden by vegetation. Balloonist Michael Wolf saw dark circles in a farmer's field and realized these were evidence of Bronze Age burial mounds.

The 52-year-old said: “In twelve years of ballooning, I have never seen anything as clear as this. It was like looking down on a map.

“I have flown over this field before, and never seen any marks. The hot weather must have created absolutely perfect conditions for seeing the marks.”