Brunel Tunnel Under River Thames

You are standing near the site of the world’s first successful tunnel built under a major, navigable river. In the early nineteenth century, London’s port was so congested with ships that a traditional bridge was impossible to build without blocking maritime trade. The engineer Marc Isambard Brunel solved this by looking to nature, specifically observing how a shipworm bored through timber hulls and lined its tunnels with a protective secretion. He adapted this concept into an iron tunnelling shield, a massive device that allowed workers to excavate through the soft, waterlogged riverbed of the Thames without the tunnel collapsing around them.