Quiz: A Look at Tunnels

Tunnels are an integral part of today’s infrastructure, conduits for transportation, water, sewage, and utilities. They have been used since antiquity, where all major ancient civilizations left some example of tunnel behind. In some ways, those ancient tunnels are more noteworthy because they were dug by hand, well before the age of mechanization. Today, tunneling crews use a variety of software and machines to build projects ranging from small-diameter utility tunnels to those large enough for highway traffic. See what you know about tunnels in this quiz.