Badaling Section, Great Wall, Beijing, China, c. 1505 AD (Ming Dynasty) — The best-preserved and most visited section of the wall was fully restored in the 1950s and sits at 1,000 meters elevation north of Beijing. Crenellated parapets and evenly spaced watchtowers here exemplify the engineering standards of the Ming Dynasty's northern frontier fortifications.
© CEphoto, Uwe Aranas, CC BY-SA 3.0, via Wikimedia Commons
