The Taipei City Walls were established in 1884. In 1875 the Qing Dynasty established the Taihoku Prefecture. Shortly thereafter, the Taihoku Prefect Chen Xing-ju ordered the foundation of a new prefectural capital, with enclosing wall in 1879. However the soil proved too soft to support so heavy a structure, and the project was halted. Subsequently, governor of Fujian Cen Yu-ying and Taiwan magistrate Liu Ao undertook successive surveys to determine the proper location of the wall's foundations. Craftsmen were recruited for the construction in 1842, and the wall was completed in 1884. Nearly five kilometers in length, it could be accessed by five gates. Jieng Fu Gate to the East; Bao Cheng Gate to the West; Li Zheng Gate to the South; Cheng En Gate to the North; and an auxiliary southern entrance known as Chueng Xi Gate. The North Gate Auxiliary South Gate, and the buttresses of the East Gate were of particularly exquisite design. In the first years of the Japanese colonial rule, the city's walls and the West Gate were destroyed as part of the cities restructuring plan. After Taiwan's retrocession in 1945, the East, South, and Auxiliary South Gates were rebuilt, but the original appearances were not maintained. The North Gate alone retains its original appearance. Its design is a 2-story closed blockhouse of solid construction with traditional Chinese wooden roof truss and streamlined carved ornamentations.

Taipei City (/ˌtaɪˈpeɪ/; [tʰǎipèi]; Chinese: 臺北市 or 台北市; pinyin: Táiběi Shì) is the capital of the Republic of China (Taiwan). Situated at the northern tip of the island of Taiwan, Taipei is located on the Tamsui River; it is about 25 km southwest of Keelung, a port city on the Pacific Ocean. It lies in the two relatively narrow valleys of the Keelung (基隆河) and Xindian (新店溪) rivers, which join to form the Tamsui River along the city's western border. The city proper (Taipei City) is home to an estimated 2,618,772 people. Taipei, New Taipei, and Keelung together form the Taipei metropolitan area with a population of 6,900,273. However, they are administered under different local governing bodies. "Taipei" sometimes refers to the whole metropolitan area, while "Taipei City" refers to the city proper. Taipei City proper is surrounded on all sides by New Taipei.

Taipei is the political, economic, and cultural center of Taiwan. The National Palace Museum which has one of the largest collections of Chinese artifacts and artworks in the world is located in Taipei. Considered to be a global city, Taipei is part of a major industrial area. Railways, high speed rail, highways, airports, and bus lines connect Taipei with all parts of the island. The city is served by two airports – Taipei Songshan and Taiwan Taoyuan.

A defensive wall is a fortification used to protect a city or settlement from potential aggressors. In ancient to modern times, they were used to enclose settlements. Generally, these are referred to as city walls or town walls, although there were also walls, such as the Great Wall of China, Hadrian's Wall, and the metaphorical Atlantic Wall, which extended far beyond the borders of a city and were used to enclose regions or mark territorial boundaries. Beyond their defensive utility, many walls also had important symbolic functions — representing the status and independence of the communities they embraced.

Existing ancient walls are almost always masonry structures, although brick and timber-built variants are also known. Depending on the topography of the area surrounding the city or the settlement the wall is intended to protect, elements of the terrain (e.g. rivers or coastlines) may be incorporated in order to make the wall more effective.

Walls may only be crossed by entering the appropriate city gate and are often supplemented with towers. In the Middle Ages, the right of a settlement to build a defensive wall was a privilege, and was usually granted by the so-called "right of crenellation"^{[citation needed]} on a medieval fortification. The practice of building these massive walls, though having its origins in prehistory, was refined during the rise of city-states, and energetic wall-building continued into the medieval period and beyond in certain parts of Europe.