Darius, king of Persia, did it in 331BC, with caltrops strewn where he thought his enemy Alexander the Great would advance.

波斯国王大流士在公元前 331 年就这样做了，在他认为他的敌人亚历山大大帝会前进的地方撒上菱角。

So just prior to the robbery, some accomplices laid out metal caltrops on all the roads connecting to the building which prevented any police cars from getting anywhere close.

所以就在抢劫发生之前，一些同伙在所有与大楼相连的道路上铺设了金属三角钉，防止警车靠近。