Feng Shan

Feng Shan, was a special ceremony performed by the emperors of China to honor heaven and earth. They would go to Mount Tai and Mount Liangfu to perform the sacrifices. The Feng sacrifice was done at the top of the mountain to honor heaven, while the Shan sacrifice was done at the foot of the mountain to honor earth. 
Completing the Feng Shan ceremony allowed the emperor to be seen as having the support of heaven. The word "feng" means "to seal", and "shan" means "to clear away". 
This ceremony is very important in religious Confucianism. According to Records of the Grand Historian, the emperor would build an altar at the top of the mountain and proclaim their legitimacy to the god of heaven during the Feng sacrifice. During the Shan sacrifice, they would clear land at the foot of the mountain to show respect to the god of earth.
This ceremony was used as a way for emperors to think about the relationship between heaven and earth. It was usually only performed during times of prosperity, with a good emperor and good omens. Some emperors refused to perform the ceremony, feeling they were unworthy of it. 
Although only the emperor was historically allowed to perform the ceremony, there were times when common people did it without permission. The general Huo Qubing even did it alone.
The Feng Shan ceremony played an important role in politics, much like the Secular Games of the Roman Empire. Both were rare and had religious significance, and were important for changing ideas about power. 
History.
Mount Tai has been a place of worship for many years, and it began in prehistoric times.
According to legends, the Yellow Emperor performed the ceremony before ascending to heaven as an immortal.
Sacrifices at Mount Tai continued through the Zhou dynasty. During the Warring States Period, both Qi and Lu leaders would carry out sacrifices at the mountain. In 219 BC, Qin Shihuang carried out what would be considered the first Feng and Shan sacrifices in celebration of uniting China.
The last recorded traditional Feng Shan was performed in 1790 by the Qianlong Emperor. There are only six verified accounts of performances throughout Chinese history.
Emperors like Wu of Han, Gaozong of Tang, and Zetian all carried out sacrifices. In modern times, a festival is held every year to celebrate the occasion with a modern light show.