@CNN: This concrete bridge is 86 feet long, took 450 hours to build, and was created entirely by a 3D printer https://t.co/27Izec6GEu
This concrete bridge is 86 feet long, took 450 hours to build, and was created entirely by a 3D printer https://t.co/27Izec6GEu
— CNN (@CNN) January 27, 2019