The Great Wall, Northeast of Beijing, China
The Great Wall has been on UNESCO's World Heritage List since 1987. The largest architectural structure in the world, it is 19.6–22.9 feet tall and approximately the same across — generally, less than 32 feet.
Its length has been reevaluated several times. In June 2012, the Chinese authorities announced their latest estimate of its length as being 13,170 miles — versus the approximate 4,038 miles reported just a few years earlier...
© CNES 2008 – DISTRIBUTION ASTRIUM SERVICES / SPOT IMAGE