The Pillars of Thárletyp

The Great Lake Thárletyp is best known for its populous waters and elaborate stone structures, arching and twining lovingly over the lake. However, muttered amongst the locals are whispers of confusion and suspicion over the origin of such things. Thárletyp was a mere decade ago, hostile to colonization or township founding - any attempts at such often resulted in violent destruction and natural disasters around the otherwise placid lake.
One of the most common suggestions comes from the carvings on the arches themselves; suspected to be the story of Thárletyp itself, or at least one of its more violent inhabitants, the ancient images depict a crude and simple story of a starving creature arriving in the bowl of the mountains, perishing, and being resurrected to keep eternal guard over its deathbed.

Summary

Scrawled across the ancient stone architecture are images depicting a crude and simple story of a starving creature arriving in the bowl of the mountains and finding a puddle with a few small, sickly fish in it. After drinking the water and finding it sour despite its clarity, the creature decries the realms above. The creature wails for many days, and, eventually, receives an answer - a storm.
Trapped in the bowl and far too weak to move, the creature can do little but accept its fate as the storm swiftly floods the bowl. As it is drowning, the creature is finally moved from its despair, and is instead enraged at what appears to be a cruel trick of the gods. Its fury triggers a transformation, shifting it into a grand monster whose appearance varies wildly from carving to carving. Regardless, the monster drags itself free of the flooded bowl and wreaks havoc upon the mountainside, until it becomes exhausted of its own rage and desperate for rest. However, wary of the sun and the heavens' fickle nature, before it retreats, it carves into one of the grand mountains holding its lake. With the stone torn by its own limbs - or teeth, depending on which carving one looks at - it constructs a seal to withhold the Great Lake Thárletyp from the heavens, denying them their right of mist and cloud.
Thus satisfied, the monster finally returned to the lake, where it lay upon a bed of silt and rock to sleep, tended by the lake's grateful, smaller, inhabitants.

Spread

The Pillars' Curse, as it is colloquially dramatized, is a fairly widespread myth; initially given to the lands surrounding Thárletyp's bowl, especially those civilizations that attempted to expand into the mountains. Travelers and traders frequenting these places soon picked up on the local legend, and carried it with them further and further abroad. While it has been warped the further and further the teller gets from Thárletyp - the most infamous and least accurate blurring the tale of the mountain lake with one of a distant meteoric field - the Pillars' Curse is still a fairly well known tale.