Crossbows are the typical distant weapons of the ancient Việt people. The bronze crossbows dated to 2,300 – 1,800 BP have been found fairly rich in Việt Nam. This period coincides with the time the Liên Châu magic crossbows appeared.

The creation of the crossbows with the “uninterruptedly holding” mechanism is an important feature that makes the arrows more powerful and threatens the enemies. This is a factor that creates “legendary” of the weaponized crossbows in An Dương King period as compared to the contemporary weapons and even to the type of crossbows used with the common bi-winged arrows. The layout of the bow wings on the supporter so that they are resilient can be considered to be a unique invention in the history of weapons. The book Lĩnh Nam chích quái (Selection of Strange Tales in Lĩnh Nam) writes: Point the bows to the enemies and they do not dare come near.

The results of the archaeological research have proved the invention of the general Cao Lỗ with numerous crossbows is real. This also demonstrates that our ancestors reached a very high level of military science 2,000 ago, which served as a base for their strength for fighting against the aggressors and this strength has been maintained up to date.