Norway Builds World’s First Floating & Largest Underwater Tunnels August 28, 2020 Canadmin Sci Tech Norway Builds World's First Floating & Largest Underwater TunnelsNorway Builds World's First Floating & Largest Underwater Tunnels- The $47Bn Highway Mega ProjectPosted by Sci-Tech World on Thursday, March 28, 2019 Sci-Tech Norway Builds World’s First Floating & Largest Underwater Tunnels- The $47Bn Highway Mega Project See less. Credit Sci-Tech World