A mudlark is someone who likes to hunt for treasures on the muddy banks of a river or any body of water. They usually search for things that have been lost or left behind, like old coins, pottery, and other interesting things. These people have a special love for the history of their city and they believe that the treasures they find can tell stories about the past. It's kind of like a big treasure hunt, but instead of looking for gold and jewels, they are looking for exciting bits of history!