Reconstruction of the Great Wall
Reconstruction of the Great Wall
Historically, the Great Wall stretches over approximately 6,400 km in total from Shanhai pass in the east to Jayu pass in the west, along a rough arc.
After hundreds of years of natural erosion and human activity, the Great Wall is vanishing. A survey shows 20% of it is in ruins and another 50% has already disappeared.
The existing locations of the Great Wall are shown as points. Their GPS positions come from Google Earth.
What is those points can tell us? What was the length of the Great Wall? How to estimate the history from the viewpoint of present?
This Demonstration shows a method for reconstructing the Great Wall by using a minimum spanning tree from the GPS points, giving a maximum distance of 6,104 km.