Sword Lake City lies between Qinghe and Langya, roughly corresponding to the modern location of Dongping Lake. The Capital is similar to its current location, whereas Yanmen Pass is in Shanxi.
Although Yanmen and the Capital both lie to the north, in reality, they form a triangle with Sword Lake City. To reach Yanmen Pass, one wouldn't pass through the Capital, so Vermilion Bird had to coax Zhao Changhe into taking a detour there.
The journey was significantly longer, especially with Zhao Changhe's habitual tactic of employing deceptive maneuvers, making detours left and right. It took so many days to head north that they gradually sensed the arrival of autumn, seeing the ears of wheat by the roadside and the golden yellow of the trees.
Just like the south, the northern plains were no better off.
