line of beacons

Guan Yu’s line of beacons is a warning system established to protect Jingzhou while he campaigns against Fancheng. It gives him a means of learning about an attack from afar, but its reliance on guards who can be deceived makes it vulnerable: Lü Meng’s disguised troops capture the sentries before they can light a beacon, allowing Wu forces to advance without warning.

Purpose and strategic setting

As Guan Yu advances against Fancheng, he recognizes that leaving Jingzhou exposed could invite an attack. He therefore establishes a chain of beacons to alert him if the region comes under threat. The system is not a passive detail of his defenses: it is meant to connect his campaign at the front with the security of territory behind him, allowing warning to travel even while he is away.

That precaution reflects the strategic problem Guan Yu faces. Success at Fancheng depends on concentrating his forces there, but doing so risks weakening the defense of Jingzhou. The beacons are his answer to that tension: they are intended to let him pursue the campaign while remaining informed of danger to his base.

How Wu plans around the warning system

When Lü Meng returns to Lukou, he learns both that the beacons stand in the way of an attack and that Jingzhou is well defended. The news alarms him, and he pretends to be ill, fearing he cannot carry out the undertaking promised to Sun Quan. Lu Xun recognizes the pretense and treats its cause as a problem that can be solved through deception rather than direct assault.

Lu Xun proposes making Guan Yu feel secure. Lü Meng is to appear to have resigned because of ill health; Lu Xun will take his place and present himself as an admirer, sending praise and expensive gifts that appeal to Guan Yu’s pride. The aim is to draw Guan Yu’s attention toward Fancheng and away from the defense of Jingzhou. Lu Xun’s flattering letter and gifts have the intended effect: Guan Yu welcomes them, and reports indicate that he has moved his troops to the siege.

The beacons are silenced

Lü Meng sets out with thirty thousand soldiers and eighty attack ships. As the fleet nears Guan Yu’s territory, some soldiers pose as merchants while the rest hide in the ships’ holds. The disguise gets them past the men guarding the line of beacons on the north shore: Guan Yu’s soldiers believe the vessels are commercial traffic and allow them through.

After nightfall, the concealed troops emerge and overwhelm the beacon guards. The guards are captured, and none escapes to raise an alarm. The invasion’s success therefore depends not on destroying the warning system from a distance, but on passing through its human defenses while appearing harmless. The beacons remain useless because those responsible for sounding the warning have been neutralized before they can act.

From lost warning to the fall of Jingzhou

The invading force continues toward Jiangling. Lü Meng persuades the captured guards to cooperate in deceiving their compatriots at the city gates. When the men arrive late at night and are recognized, the gates are opened; once inside, they set fires to create confusion and signal the rest of the troops. The city is in Lü Meng’s hands before dawn.

Guan Yu’s warning network is thus defeated in stages: first its sentries are misled and captured, then those captives help the invading force gain entry to Jiangling. No beacon is lit to announce the danger. The system’s failure helps conceal the attack while Guan Yu is occupied with Fancheng, turning a precaution intended to protect his rear into a measure whose absence of warning leaves him unable to respond in time. The episode makes clear that a defensive network depends not only on its physical reach, but also on the alertness and trustworthiness of the people who operate it.