Fortification of the Ming Xuanfu Garrison

Timeline

1. 1428Xuanfu · ZhangjiakouIn Xuande 3, the Xuanzong Emperor personally led the capital army on a tour of Xuanfu, defeating Oirat incursions, and ordered the construction of fortresses such as Yongning and Longqing and the addition of beacon towers, strengthening defenses along the Xuanfu–Dushikou line. This established the Xuande reign's northern strategy of defense-first, with passes and fortresses linked in mutual support.
2. 1430–1434Dushikou · ChichengWithin the jurisdiction of the Xuanfu Garrison, the court built and repaired walled passes and beacon towers, linking the defense line from Juyong Pass to Datong. Although continuous brick-and-stone frontier walls of the Jiajing era had not yet been formed, military fortresses, smoke beacons, and passes already constituted an effective in-depth defense, blocking Mongol cavalry routes southward.
3. 1434Datong · DatongIn the autumn and winter of Xuande 9, the Xuanzong Emperor made his final northern tour of the Xuanfu–Datong area, reviewing frontier troops and assessing the joint defense posture of the Xuanfu and Datong garrisons. Several months after returning to the capital he fell ill and died, but the Xuanfu defense system had already reached completion, providing a foundation for northern defense in the Zhengtong reign.