During the 18th century, the practice of scavenging the muddy River Thames riverside for coal, bits of old iron, or any other item of value that may have fallen from passing ships came to be known as Mudlarking. Historically, Mudlarks were usually children and those who were destitute looking desperately for any item that they could sell for a profit. Today, the Thames foreshore is probably one of the biggest archaeological sites in the world, and modern-day Mudlarks patiently hunt for treasures from London’s ancient past along the river’s shoreline. Anyone can search for lost treasures along the Thames using their eyes and hands as their primary searching tools, but if you are planning to go metal detecting or digging with any kind of implement on the Thames foreshore you must have a permit from the Port of London Authority (PLA). All Mudlarks have to declare their finds to The Museum of London, which now holds over 200 personally discovered objects in its Medieval Gallery alone. Amongst the historic items which have been found are Tudor bricks, 18th Century clay pipes, coins, chain mail and Georgian jewellery.