The river of Labes was also known as the River of Gold in Pulgasari.
A lava river that flowed under the mountains of Bothal, it was the source of all the special ores and minerals that had made Bothal one of the richest countries in the world.
Its heat was used to light up the hearths of a smithy, while the volcanic rocks from it were used to fertilize the lands above, resulting in abundant harvest each time.
It was the life of the dwarves.
It provided them with sustainability when the world had ignored them.
It was the vein of earth that directly brought the gift from the earth's core, into the hands of the dwarves.
All of which became the reason why the dwarves had chosen to seal up all the access points to the river. It was impossible to get in or get out.