Midgardsormen
With an ox head for bait, Tor hooked the serpent that circles the world. Pale with fear, the giant beside him cut the line.
The sea round the world, in the Norse myths
Long ago, the Norse myths say, Loki had three terrible children with a giantess: a wolf, the queen of the dead, and a serpent. The gods wanted those monsters under their control. So they threw the serpent into the deep sea that runs round Midgard, the world of men. There it lay, eating and growing, until it reached all the way round the world and could bite its own tail. That gave it its name, Midgardsormen, the Midgard serpent.
Tor, the thunder god, was its greatest enemy. One day he went fishing with the giant Hyme, and he took the head of one of Hyme's oxen for bait. Out at sea the serpent bit, and the hook stuck fast. Tor pulled so hard that his feet went through the bottom of the boat and stood on the sea floor. The serpent opened its jaws and spat poison. Tor raised his hammer to strike, but the line was cut, and the serpent slid back into the deep.
Tor waded ashore with nothing, but the myths say the two will meet once more. At Ragnarok, the end of the world, the serpent will crawl up onto the land. Tor will kill it at last, and then fall dead himself from its poison. The tale was known all over the Norse world. Brage, the oldest Norwegian poet whose verses survive, told it in the 800s. And on a carved stone in Sweden, Tor still stands in his boat, his foot through its bottom.