Dingdu Peak - Niuxin Mountain is seventy li west of the county seat

Dingdu Peak is located northeast of Sangyu Village, Mentougou District, with an altitude of 680 meters. It is situated at 116°02'40" E, 39°54'40" N. Also known as Niuxin Mountain, Guacaojian, Lifengxi, Wangdu Peak, Shishan, etc., it is commonly called Niuxintuo. The *Wanshu Zaji* states, "Niuxin Mountain is seventy li west of the county seat," referring to this mountain. Later, due to the legend that Prince Zhu Di of Yan established Beijing from here, it was renamed "Dingdu Peak." Emperor Yongle of the Ming Dynasty, after climbing this mountain, exclaimed, "The view from this peak is unparalleled; it is a gift from heaven!" There are two walking trails and one road within the scenic area, both leading to Dingdu Pavilion. The road is approximately 4 kilometers long, while the walking trails are divided into east and west routes. The east route is about 8 kilometers long, passing through Dajunwutai, Xiaojunwutai, and Wangjingtai, among others. The west route is about 4 kilometers long, passing through Wangshitai and Guanghui Temple, among others. Dingdu Pavilion covers an area of 550 square meters, with a building area of 2,400 square meters. The pavilion is 33.9 meters high and has six stories, with the exterior showing three stories. It is a traditional Chinese architectural style with multiple bracket sets and a hipped roof. Standing atop Dingdu Peak, one is surrounded by layered mountains and rolling hills; the mountains are dotted with strange rocks and blooming peach trees. From the pavilion, one can see the straight Chang'an Avenue leading to western Beijing. Dingdu Pavilion is at the same latitude as Chang'an Avenue, and iconic Beijing landmarks such as the TV Tower, China World Trade Center Phase III, and the new CCTV headquarters are clearly visible. One can imagine the scene when Prince Zhu Di of Yan climbed the peak, surveying the landscape and planning his grand schemes – a truly exhilarating experience. Now, I am delighted to climb Dingdu Peak and ascend Dingdu Pavilion. The view of Beijing is picturesque, like a fairyland. As the old saying goes, "He who has not climbed the Great Wall is not a true hero," and now I would add: "Only when you reach Dingdu Pavilion do you truly understand Beijing." How did Yao Guangxiao raise his flag to secure Beijing, and how did he arrive at the saying, "Beijing began at the foot of the mountain and was completed at the foot of the mountain"? Come to Dingdu Pavilion and the answers will be revealed. It's the best place to admire the autumn leaves and enjoy panoramic views of Beijing; there's also a saying that the Grand Canal is to the east and Dingdu Pavilion to the west. With its fresh air and high concentration of negative oxygen ions, it's an ideal place for leisure and entertainment.