Every month we appease our inner nerd by digging up some local statistics

This month we went for ancient ice roads:

  • Historians believe 70km of ice roads were used in the construction of the Forbidden City.
  • 16th century Chinese wagons couldn’t move stones heavier than 96 tons.
  • -3.7°C average temperatures in January at the time could create ice strong enough to bear the weight of heavier stones.
  • In 1557 a 123-ton stone was transported over 28 days to the Forbidden City from a quarry by ice sledge, according to a 500-year-old Chinese record.
  • Teams of at least 46 men pulled the stones and kept the ice roads slick with water from wells dug every half-mile.

Source: Nationalgeographic.com

A version of this article appears in the January 2014 issue of the Beijinger

Image: Micky Pan