RACHEL MARTIN, HOST:
In the United Kingdom, archeologists have made a number of significant discoveries recently, from the battered remains of King Richard III buried beneath a parking lot, to a 14th century cemetery for plague victims. British soil is full of traces of the past. And in London, one has to look no further than the Thames, the river that runs through the heart of the city.
Reporter Christopher Werth has the story.
(SOUNDBITE OF THE RIVER THAMES)
CHRISTOPHER WERTH, BYLINE: The Thames runs deep in Western history. The Romans founded London on its banks 2,000 years ago. Since then, the Vikings and Normans have set sail from here. It was the thoroughfare of the Industrial Revolution.
And on a brisk, windy morning, Mike Woodham walks the water's edge with a metal detector in search of things humanity has left behind.
(SOUNDBITE OF METAL DETECTOR BEEPS)
MIKE WOODHAM: That's a strong signal. Let's give that a little dig and see what we got.
WERTH: Woodham belongs to a long London tradition of so-called mudlarks, who populate the riverbed when the tide is out. Centuries ago, mudlarks scavenged for bits of coal, scrap iron or other items of value. Today, they're essentially history buffs who scour the Thames for anything that offers a glimpse into London's past.
(SOUNDBITE OF DIGGING)
WOODHAM: And that looks like a - it's a lead token.
WERTH: A lead token?
WOODHAM: Yeah, they used to use them for ferry crossings - the water boatmen. They all had their own individual little lead tokens for payment.
WERTH: Around what period would that have been?
WOODHAM: These all dated roughly the same, about 1550.
WERTH: So there it is just sitting on the beach.
WOODHAM: Just sitting there for 500 years. That's what amazes me. Like, 500 years ago, somebody dropped something and you find it. You can just walk along the ground and find stuff. There's just been life down here for thousands of years. Nine times out of 10 it's junk. But that one time it's something nice and that's what we all dig for - that one nice thing.
WERTH: And when you find something rare, Woodham says - like an Elizabethan coin, a penny, that dates back centuries - you ask yourself questions about the person who lost it.
WOODHAM: Me personally, I think how did it impact on their life because if we lose a penny today it means nothing. You know, back in the 1500s a penny was worth quite a lot. So if you lost your wages for that week, how are you going to support your family? That's what I think about.
WERTH: Mudlarks have unearthed all sorts of things in the Thames; from Bronze Age ceremonial objects and 15th-century swords, to tiny Roman statuettes and munitions from the Second World War.
Last year's find of the year was a piece of a 30,000-year-old Woolly Rhinoceros skull pulled out of the riverbed near London Bridge.
By law, mudlarks need a license to dig on the riverside. And under a voluntary program in the U.K., called the Portable Antiquities Scheme, significant finds are supposed to be reported here...
(SOUNDBITE OF SCHOOL GROUP)
UNIDENTIFIED CHILD: Here's a gold spoon.
WERTH: ...the Museum of London, just a short walk from the Thames.
Roy Stephenson, the manager of the archeological archives, leads me past school groups to display cases full of artifacts.
ROY STEPHENSON: A lot of the things in the gallery here have come from the river.
WERTH: He says mudlarks' discoveries help fill gaps in the museum's collection. That's because, on land, metal objects were often melted down and reused. But if something fell in the river, it essentially vanished. As a result, Stephenson says much of what's known, for example, about childhood in medieval London comes from pewter toys lost in the Thames centuries ago and found by mudlarks today.
STEPHENSON: You can see there's little lidded jugs, little pewter plates. You know, if you were a kid, these are the pocket money toys of the day. We are getting to see some absolutely fascinating things that come off the foreshore.
WERTH: Mudlarks are allowed to dig roughly four feet into the foreshore or the banks of the Thames. And that's angered archeologists like Paul Barford. He says all that digging has destroyed the centuries-old layers of earth in which artifacts are buried and help give them their historical context.
PAUL BARFORD: The foreshore of London has been so thoroughly dug over and so deeply, that I doubt there's very much archaeology left there. Any archeological layers, any archeological deposits that were there, they've gone. We've lost it because of these mudlarks.
WERTH: Today, Barford says that same destruction is happening on land to important archeological sites all over Britain. He believes over 11 million artifacts have gone unreported by hobbyists with metal detectors over the past several decades.
He says much of them end up in private collections or for sale online. He recently spotted a pair of Anglo-Saxon gold rings on eBay. All of which is why he wants tougher restrictions on metal detecting in the U.K.
BARFORD: Britain is the only country which does this. All the other countries of Europe, like Poland or France, if you go out with a spade you could get locked up for it. And in England, they pat you on the head and say, thank you, well done for digging a big hole in this archeological site and bringing us these lovely coins. People just do not understand that with this goes a wholesale destruction of the archeological record.
WERTH: It is best if detectorists just pick up what's on the ground, instead of digging for finds, says Roy Stephenson at the Museum of London. He admits the British system has its flaws but he believes it does work to some extent.
STEPHENSON: We don't know what isn't coming to us. So, you know, there'll be a portion of that picture that we're not seeing, but we're not losing everything. We're seeing quite a lot of it, and some of it we're keeping for our collections and for sound academic study as well.
(SOUNDBITE OF DIGGING)
WERTH: On the banks of the Thames, Mike Woodham, the mudlark, is still looking for that one nice thing.
WOODHAM: Whatever it is, it's down deep...
(SOUNDBITE OF DIGGING)
WOODHAM: Archeologists say metal detecting is bad. And metal detectors say archeologists are bad.
WOODHAM: They don't like us being here because they don't see us as professional. But I personally think they're just misinformed. All we're doing is helping them by finding stuff. So in a way we are archeologists, as well. If they respect me, I respect them.
WERTH: And with that, Woodham calls it a day. The tide has begun to creep back over the riverbank. The Thames rises and falls more than 20 feet, twice a day, just as it's done for thousands of years.
For NPR News, I'm Christopher Werth in London.
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