Yongding Gate, which literally translates as "the gate of perpetual peace," sits at the south end of the Central Axis of Beijing.

Having formerly served as the front gate of Beijing's old city wall guarding the outskirts of the capital, the structure has a long history and was of crucial military significance.

Yongding Gate Tower was built in 1553 in the middle of the Ming Dynasty (1368-1644 AD). A barbican, or outer defensive work, was constructed around a decade later, and an Archery Tower was completed in 1750 during the subsequent Qing Dynasty (1644-1911 AD). This three-building complex stood along the south city wall of old Beijing for more than 200 years, until it was dismantled in 1957 to help improve traffic conditions.

Yongding Gate serves as the main entrance through the outer perimeter of Beijing. Its gate tower is the largest and highest among the seven gates along the city wall, featuring the most complicated structure and built in a prime location to access the inner city. 

To restore the landscape of old Beijing and maintain the integrity of the Central Axis, the gate tower of Yongding Gate was rebuilt in 2004 based on charts and other materials showing its previous structure. The current version stands 26 meters tall and measures 31 meters in length, surrounded by gingko and pine trees, not to mention a large square to the south where local residents can relax.

The Beijing Central Axis measures around 7.8km in length and begins at the Bell and Drum Tower. It runs south through Tian'anmen Square, the Palace Museum, Wanning Bridge and Zhengyang Gate before ending at Yongding Gate.

Dubbed the "backbone" of old Beijing, this ancient axis is now bidding for UNESCO World Heritage status and Beijing authorities have launched a plan to better preserve this historical area.