The capital of Yan was located about 45 km (28 mi) to the south of Ji, in the village of Dongjialin in Liulihe Township of Fangshan District, where a large walled settlement and over 200 tombs of nobility have been unearthed.
Among the most significant artifacts from the Liulihe Site is the three-legged bronze Jin Ding whose inscriptions recount the journey of Jin, who was sent by Ji Ke to deliver a batch of food and drink to his father, Ji Shi, in the Zhou capital.
It is believed that the seat of Ji, called the City of Ji or Jicheng (蓟城/薊城), was located in the southwestern part of present-day urban Beijing, just south of Guang'anmen in Xicheng and Fengtai Districts.
Several historical accounts mention a "Hill of Ji" northwest of the city, which would correspond to the large mound at the White Cloud Abbey, outside Xibianmen about 4 km (2.5 mi) north of Guang'anmen.
Like subsequent rulers of Beijing, the Yan also faced the threat of invasions by the Shanrong steppe nomads, and built walled fortifications across its northern frontier.
Remnants of the Yan walls in Changping County date to 283 BC.
The triumph of the Yellow Emperor over the Yan Emperor at Banquan united the two Emperors' tribes and gave rise to the Huaxia or Chinese nation, which then defeated Chiyou and the Nine Li tribes in the Battle of Zhuolu, possibly at Zhuolu, 75 km (47 mi) west of Yanqing in Hebei Province.