The Great Wall of China is the longest structure ever built by humans. ✨🎤All its parts together measure about twenty-one thousand kilometers. ✨🎤That is half the distance around the Earth. ✨🎤

Chinese emperors built the wall to stop riders from the northern steppe. ✨🎤Many of those riders were the ancestors of modern Mongolians. ✨🎤The wall had watchtowers, and guards sent smoke signals when they saw danger. ✨🎤A message could travel hundreds of kilometers in a few hours — from tower to tower. ✨🎤

Building the wall took almost two thousand years. ✨🎤Millions of workers carried every stone by hand. ✨🎤Today the wall no longer stops anyone — instead, it invites millions of visitors every year. ✨🎤