Telegraph.co.uk examines some of the costliest, biggest, tallest and longest man-made structures that exist in the world today.
From tunnels to bridges, railways to statues, we count down the top five and share some incredible facts and figures about them.
This video looks at the top five longest walls in the world, including the Ancient Walls of Babylon that stretch over 56 miles, and Hadrian’s Wall that took 15,000 men and over six years to build.

source: telegraph.co.uk

360° view of Hadrian’s Wall (chrome browser)