2018 U.K. Heat Wave Exposed 5,000 Years of History

Complete Article From the publisher.

Archaeology
On very rare occasions, during unusually hot, dry summers, normally hidden features can appear on the landscape. This can occur in two ways. Areas where the remains of buildings lie just underground or where a stretch of land has been repeatedly walked upon are always drier. During a heat wave, vegetation there will wither more quickly, creating brown parch marks that contrast with the surrounding grassy areas.