The Loushan Pass is mentioned in "Remembering the Beauty of Qin" as a significant historical site located in the Shaanxi province of China. This strategic pass, which played a crucial role during the Qin Dynasty, is highlighted for its strategic importance in the defense of the empire against invasions from the north. The book, which is a collection of essays on the history and culture of the Qin Dynasty, places the Loushan Pass within the broader context of the dynasty's military and political strategies.

The mention of Loushan Pass in "Remembering the Beauty of Qin" is significant because it underscores the dynasty's focus on fortifying its borders to protect against the Xiongnu, a nomadic people who frequently threatened the empire's stability. Historical records indicate that the construction of the Great Wall, which includes the Loushan Pass, began during the reign of Emperor Qin Shi Huang (259–210 BCE). The Great Wall was an extensive system of fortifications designed to protect the Chinese empire from invasions, and the Loushan Pass was a key component of this defensive network.

According to the Chinese historian Sima Qian, the Loushan Pass was strategically positioned to control the trade routes and to monitor the movements of the Xiongnu. The pass's location, which sits at an altitude of approximately 1,500 meters, provided a natural barrier against invaders. The pass's significance is further underscored by its mention in the "Records of the Grand Historian," a foundational text in Chinese history, which highlights its role in the defense of the empire.

The historical data on the Loushan Pass and its importance during the Qin Dynasty is supported by archaeological evidence. Excavations at the site have revealed remnants of the Great Wall, including watchtowers, fortresses, and defensive structures. These findings provide tangible evidence of the pass's strategic importance and its role in the broader context of the Great Wall's defensive system.

In conclusion, the Loushan Pass is mentioned in "Remembering the Beauty of Qin" as a pivotal site in the defense of the Qin Dynasty against the Xiongnu. The book's emphasis on the pass's strategic importance is well-supported by historical records and archaeological evidence, making it a significant reference point for understanding the military and political strategies of the dynasty.