Twelve Heavenly Paces of the Colossus
The Anguista mountain range is said to have been created during the war between the primordials and the gods. It acts as a natural border between the different nations of Silurnia, and its rocky peaks make it all but impossible for these borders to be traversed.
While there are several small breaks (less than a mile wide), there is a significantly large artificial tunnel through the border between Ordovicia and Rhodanthus, made by dwarves. They were commissioned by King Ozo the Demon of Rhodanthus, who wanted to wage war against the Ordovicians, but upon completing the tunnel the dwarves refused to carve any more as they believed the mountains were too sacred and beautiful to be touched by their unworthy hands. (King Ozo was defeated by the Ordovician’s superior military anyway.)
The story detailing the creation of the mountain range involves the story where Rhodan slew Sthenys. When Rhodan decapitated the head of the Grand Serpent, its body began to petrify. Worried that the falling stones would harm his mortal allies, he broke off the hilt of his blade, stabbed it through the middle of the body and threw it like a weighted ribbon toward the coast. The body completely petrified before it reached its destination, and the stony body cracked into countless pieces, forming the Anguista Mountains.