The oldest section of Great Wall's, one of the seven wonders of the world was built between 770 BC to 476 BC in the ancient state of Qi, hence the section is often called the Great Wall of Qi.
After a seven-month investigation, the 620 km stretch of the Great Wall of Qi from Jinan City, capital of east China's Shandong Province, to Qingdao, a coastal city of Shandong was found to be damaged, said archaeologist Li Zhenguang, head of the investigation team.
The results laid the foundation for the preservation of the Great Wall of Qi, which had constantly been damaged by local residents, he said.
After identifying the exact length and location of the entire Great Wall, a system can be established to hold local governments to account for vandalism, Li said.
The investigation is part of a plan to better preserve the Great Wall by the State Administration of Cultural Heritage.
According to the plan, China's knowledge of the Great Wall, regarded as the longest in world is very limited and many parts of it need to be explored before a comprehensive database can be built to better preserve it, official Xinhua reported.
The Great Wall consisting of a series of stone and earthen fortification was built over a period of time and stretches up to about 8,851.8 km mainly to prevent external invasions