Zhonghua Gate (Chinese Gate) is the south gate of Nanjing City, Jiangsu Province. A precious cultural relic, Zhonghua Gate has the double distinction of being the biggest castle-style city gate in China and a structural element of the most complicated castle in the world. It is the castle's magnificent scale, delicate structure, and the great skill with which it was built that bequeath it an important place in China's military and architectural traditions.

Construction of the castle took twenty-one years, from 1366 to 1387. The gate, originally called the 'Gate of Gathering Treasure' carries a legend from the time of its creation in the early Ming Dynasty. According to the legend, when Zhu Yuanzhang, the first emperor of the Ming Dynasty (1368-1644), had the gate built, the ground kept sinking. The gate collapsed again and again. It was not until a treasure bowl was buried under the gate that it stood firm. In 1931, to commemorate the revolution of 1911 and the Republic of China (1919-1949) that emerged as a result, the Gate of Gathering Treasure was renamed Zhonghua Gate. In Chinese Pinyin, Republic of China is written as Zhonghua Minguo.

Nanjing was the capital of China during the Ming Dynasty under the reign of Emperor Zhu Yuanzhang. (Zhu Di, the son of Zhu Yuanzhang, moved the capital to Beijing in 1420.) In 1366, Zhu Yuanzhang began to build a wall around the city of Nanjing to defend it from attack. The Gate of Gathering Treasure (Zhonghua Gate) was built on the site of a previous gate, the south gate of the city built during the Later Tang Dynasty (923 - 936). The new gate, the grandest among the thirteen gates of the new castle, was an architecturally complex structure composed of three closed courtyards and four arched doors serving as the entrance. There were double paneled wooden doors and with additional stone door set behind. If the enemy broke through the wooden doors, they could be separated and trapped in the three closed courtyards upon dropping the stone doors.