Hangu Pass 函谷关

Hangu Pass is located in Wangduo Village, 15 kilometers north of Lingbao City, Henan Province, approximately 75 kilometers from Sanmenxia City. It sits on the "Ancient Chang'an Road" and is close to the banks of the Yellow River. The pass gets its name from its location in a deep, narrow gorge, where the terrain is as steep and enclosed as a "letter box" (han, 函 in Chinese).

Hangu Pass is strategically situated with high plateaus to the west, sheer ravines to the east, the Qinling Mountains to the south, and the Yellow River blocking the north. It is one of the earliest-built majestic passes in China, dating back to the Spring and Autumn Period and the Warring States Period. As a vital gateway connecting Luoyang in the east and Chang'an in the west, it has long been hailed as a military stronghold, with descriptions like "Heaven opens Hangu to strengthen Guanzhong; ten thousand valleys stir dust, sweeping northward into emptiness" and "Twin peaks tower beside the great river; Hangu has always been a battlefield." It has been a fiercely contested spot for military forces throughout history:

Beyond its military significance, Hangu Pass was a key hub for cultural and economic exchanges between the Central Plains and northwest China in ancient times. It is also where Laozi, the ancient Chinese thinker and philosopher, wrote his 5,000-character Tao Te Ching. For thousands of years, Taoist followers from home and abroad have made pilgrimages here to honor their ancestors. The pass is intertwined with historical stories and legends, such as "Crowing like a rooster and stealing like a dog" (a metaphor for petty tricks), "Gongsun Long's 'White Horse' paradox," and "Emperor Xuanzong of Tang changing the era name." Celebrities like Emperor Taizong of Tang, Emperor Xuanzong of Tang, Sima Qian, Li Bai, Du Fu, Bai Juyi, and Sima Guang visited Hangu Pass and wrote poems about it, with over a hundred such works surviving to this day.

Wangqi Tai, also known as "Zhanzi Lou" (Tower of Gazing at Purple), is said to be where Yin Xi, the guardian of Hangu Pass, climbed to observe celestial phenomena. Before Laozi arrived at Hangu Pass, Yin Xi saw purple auras spreading from the east, knowing a sage was approaching—soon after, Laozi indeed arrived riding a green ox. This gave rise to the idiom "Purple auras come from the east" (a sign of good fortune). The Tang poet Du Fu wrote in Autumn Thoughts, "Westward, the Queen Mother descends from Yaochi; eastward, purple auras fill Hangu Pass." To commemorate Yin Xi, the mound where he watched for auras was named "Wangqi Tai." During the Tang Dynasty, a 3-zhang-tall (about 10 meters) Zhanzi Lou was built here. The tower was destroyed in wars during the Republic of China era; the structure seen today is a recent 仿古 (archaeological-style) reconstruction.

Taichu Palace is located beside the east gate of Hangu Pass. Legend has it that after Yin Xi welcomed Laozi to the pass and treated him as a teacher, he begged Laozi to write a book. Laozi then composed the Tao Te Ching here. This profound work had a profound impact on later generations. To commemorate this event, people built Taichu Palace on the site where Laozi wrote the text. It was once a Taoist temple.

Taichu Palace is a classical hall-style building, with mythical beasts like unicorns, lions, and tigers sculpted on the roof ridges and gable eaves, each vivid and lifelike. The roof beams crisscross, and the rafters are arranged in an orderly yet complex framework, with a spacious hall unsupported by central pillars. Historical records indicate that Taichu Palace was first built during the Western Zhou Dynasty. The main hall standing today dates back to before the Tang Dynasty, with renovations in the Yuan, Ming, and Qing dynasties. Two stone steles remain in Taichu Palace: one erected in 1300 (the 4th year of the Dade era of the Yuan Dynasty) and another in 1653 (the 10th year of the Shunzhi era of the Qing Dynasty), both recording the story of Laozi riding a green ox through Hangu Pass.