Figure 3. The bridges built in Xi'an (Sourced from https://kknews.cc/travel/oo8bjpm.html)

From

The World’s Oldest Bridges - Mycenaean Bridges

Karas Slawomir, Nien-Tsu Tuan

American Journal of Civil Engineering and Architecture. 2017, 5(6), 237-244 doi:10.12691/ajcea-5-6-3