Sword Bridge
le Pont de l'Espee
The more perilous of the two bridges into Gore, it was like a sharp sword. No man before Lancelot had ever succeeded in crossing it. Chrétien's description rather clearly equates it with the "pont despee" of the Vulgate.
Chrétien compares the water racing beneath the Sword Bridge with the Devil's river: black, thunderous, turgid, deep, and ready to swallow anything that might fall into it. (By contrast, the river at the Water Bridge must have been calm and quiet.)
The Sword Bridge itself consisted of one great, gleaming sword, as long as two lances, nailed at each end to a treetrunk. On the far side, two lions or leopards waited, tied to a stone slab. Ignoring all warnings, Lancelot stripped the armor from his hands, legs, and feet so as to get a better purchase on the metal with his bare hands, feet and knees, shrewdly preferring cuts to a plunge into the river. Once on the other side, he found the lions gone and, using his ring, proved that they were mere delusory enchantment.
Lancelot's Ring | The Legend of King Arthur