Heritage groups say one of the countryside’s most famous monuments is “under attack” from illegal metal detectorists hunting for buried treasure. But what is “nighthawking” – and is it robbing us of our past? “See a penny, pick it up and all that day you’ll have good luck” – it’s something we’ve all told ourselves on those harmless occasions we’ve spotted small change on the ground. But there are times when pocketing the odd silver or gold coin truly breaks the law. Illegal metal detecting – or “nighthawking” as it is more commonly known – is sweeping the spine of the east of England, heritage groups say, robbing us of our chance to examine the past and causing damage and strife to landowners. England’s earliest settlements – areas such as Lincolnshire, Sussex, East Anglia and Kent – are some of those suffering the most at the hands of criminals churning up the land in the hope of finding valuable relics left by our ancestors. Hadrian’s Wall in the Northumberland National Park is one of the most recent places to come under attack, with unlawful excavations being carried out at Steel Rigg and Peel Crags. Though it is only the second time it has been targeted in five years, the site is listed as a Scheduled Ancient Monument – an archaeologically and nationally important location where it is a criminal offence to use metal detecting equipment without permission from English Heritage.