The Great Wall of China is disappearing—around 30 percent is already gone due to natural erosion and unchecked human activity.

Research conducted by the China Great Wall Society showed that only around 8 percent of the Great Wall built during the Ming Dynasty, the most visible section of the Great Wall today, is well preserved, reported OneIndia.

The Great Wall can hardly be considered a "wall" as it exists today. Instead of a single unbroken structure, it has various sections, thousands of kilometers each, from Shanhaiguan on the east coast to Jiayuguan on the edge of the Gobi desert.

In certain places it is so worn down that estimates of its total length vary from 9,000 to 21,000 kilometers, depending on if missing sections are included, according to NDTV.

Construction of the Great Wall began in the third century B.C., but nearly 6,300 kilometers were built during the Ming Dynasty (1368-1644), according to Yahoo News.

Beijing Times reported that out of the initial length, 1,962 kilometers either eroded or was already destroyed for various reasons.

Nearly one-third of the wall has given way due to erosion from rain. Furthermore, trees and grass growing in the cracks have only served to accelerate the process.

Similarly, humans had a profound effect on the wall as well. Illegal trade and the practice of stealing bricks caused damage to the wall. It was even reported that some of the bricks stolen from the wall were used to build houses.

Local governments reportedly only focus on repairing the sections of the Great Wall that attract the most visitors, leaving the less popular parts of the wall to crumble.