BBC:

Ancient hillforts and Roman settlements have been revealed by the heatwave. The dry spell has left parched fields with unmistakable “crop marks” painted into the landscape.

The Royal Commission on the Ancient and Historical Monuments of Wales (RCAHMW) has been busy recording the details – before they disappear when it next rains.

Sites across Wales have been captured from the air. The crop marks are made by vegetation drawing on better nutrients and water supplies trapped in long-gone fortification ditches – leading to lush green growth that stands out.

This was really interesting and a fascinating way to discover these ancient ruins.