The Big Digs of the 21st Century
Some of Soverinsky's picks are purely hypothetical, such as a transatlantic tunnel from Manhattan to London. Others are inarguably impressive, such as Turkey's Marmaray Tube Tunnel:
"The tunnel, which will connect Asia to Europe, is routed near the North Anatolian Fault, which according to experts has greater than a 60-percent chance of generating a sizable seismic event within the next 30 years. As a result, while much of the tunnel will bore through rock, a mile-long section under the Istanbul Strait will be encased in an immersed tube along the seabed. This underwater habitrail will integrate flexible, steel plate joints designed to withstand major quakes."
The U.S. Bicycle Route System is another interesting choice, coming in at #3.