While not much of an obstacle for infantry, it was uncrossable for Soviet tanks. The "anti-game" rule dissuades opponents to make an uncrossable line. He warns that "Linbeck Gill is uncrossable dryshod after rain". Irreducible complexity can be seen as equivalent to an "uncrossable valley" in a fitness landscape. The bridge was uncrossable in 2006 because of the risk of collapse.