Introduction to the ancient battlefield: Go southwest for about 60 kilometers from Tianshui to reach the Mumendao ancient battlefield site. Although this place is now desolate, the history of more than 1,600 years ago cannot be erased. In 231 AD, Zhuge Liang sent troops out of Qishan for the fourth time. Emperor Wei Ming sent the wise commander Sima Yi to fight against him. However, Zhuge Liang was "unsuccessful". When he led the Shu army to retreat to the Mumen area, he saw the Wei army chasing closely. Zhuge Liang observed the terrain here and found an ambush. He planned to send Wei Yan with 10,000 troops and 1,000 more troops on the road he must pass. The archers arrived at the wooden doorway first, and then led all their troops back. Sima Yi decided to pursue the Shu army, sending Zhang He with 10,000 troops as the vanguard, and himself with 30,000 troops as the rear. Zhang He took the lead and pursued forward, only to see Wei Yan leading thousands of people to press the team. Zhang He pursued Wei Yan closely. The Shu soldiers ran into the wooden door road, and the Wei soldiers also took advantage of the victory and pursued them into the wooden door road. Suddenly there was a drum sound, and the Shu soldiers on the cliffs on both sides fired their crossbows. The Wei soldiers were in chaos, and Zhang He was hit by an arrow and fell from his horse. This was the famous battle of "Mumen Road", and later generations called this place "Mumen Yagui".