Throughout Chinese history each kingdom built its own wall to protect its citizenry. In totality Great Walls were built in China for 22 centuries and they spanned more than 13,000 miles. As each kingdom fell, the conquerers joined the sections of each Great Wall to each other as a deterrent to keep Mongol hordes out of the kingdoms. Historians estimate that more than 1.5 million soldiers and laborer worked on the wall during the Ming dynasty era.
It's Greater than you can Imagine
Around Beijing there are 10 places that you can see and hike on various sections of the Great Wall. There is even a section of the wall that you can tour at night. For the athletically inclined there is even a section of wall that hosts the annual Great Wall marathon. Most of the Great Wall sites are a couple of hours drive out of Beijing and there are multiple tour agencies that are happy to accommodate.
Sections of the Great Wall run through many different Chinese provinces. In some areas there are entire sections of the wall that are missing as people dismantled it to build houses during the great famine just after Mao took control of China. The wall is truly magnificent and there is a section of wall that you can visit that will suit your curiosity.