The Annan Waters is the name of the river that separates Gunnerkrigg Court from Gillitie Wood. It lies at the bottom of a vast gorge spanned by a long bridge with bright lights and no railing. It is possible that the waters have mystical properties, such as impeding the travel of etheric beings.
The Waters, along with the gorge, were created by Coyote when he first arrived in the Wood. When he found out that the Court was trying to tame the residents of the Forest, he scored the earth with his claws in order to separate them.
The Annan River is an actual river in Scotland. According to Wikipedia ,' '"The Annan makes several appearances in folk songs, and in most appears as a malevolent force, drowning those who try to cross it. One of the most well recorded is 'Annan Waters' in which the Annan Waters allows the protagonist passage upon the promise that he may have the hero's "precious bones on my return." Kate Rusby (mentioned by Tom Siddell as the accent inspiration for Antimony ) has recorded a version of this song. The song tells a story similar to that of Jeanne and her lover: "I must cross the stream tonight/Or never more I'll see my lady/...And he has tried to swim that stream/And he swam on both strong and steady/But the river was broad and strength did fail/And he never saw his bonny lady/...For you broke beneath my true love's hand/When strength did fail and limbs did tire/...And woe betide you Annan Waters/By night you are a gloomy river/And over you I'll build a bridge/That never more true love can sever."