washington dc

  • 8 Massive Tunnels Being Built Right Now

    8 Massive Tunnels Being Built Right Now

    Now that we know it was an 20cm steel pipe that brought the world’s largest-diameter tunnelling machine to a halt up in Seattle, we can no longer fantasise about Bertha unearthing a five-storey-tall buried locomotive. But we can look at something almost as fascinating: The other giant holes that are currently being churned through the…