Vasco da Gama Bridge, Portugal - 56,381 feet: Lisbon's Vasco da Gama Bridge is the longest in Europe, spanning a total distance of 10.7 miles. Taking three years to complete, the bridge opened for traffic in 1998 to celebrate the 500th anniversary of Vasco da Gama's discovery of the maritime route from Europe to India.
A type of wave that can travel through empty space as well as through matter is electromagnetic wave.
Photons travel through empty space at a speed of approximately 186,282miles (299,792 kilometers) per second. This is true no matter what the electromagnetic wavelength. In media other than a vacuum, the speed is reduced.