The Deeprun Crevasse is a deep canyon carved by the Myrfrus, or Deeprun, River in eastern Iobaria's Dvezda Marches. Over three miles wide in places and flanked with treacherous cliffs, the floor of the Deeprun Crevasse is a rocky wasteland filled with small crags, snowdrifts, and broken blocks of ice washed downstream by the Myrfrus.1
The northern reaches of the Deeprun Crevasse are lined with almost-glacial ice on either side of the Myrfrus River. Hoarfrost coats much of the surrounding wastelands, and snow drifts up to fifty feet high pile up along the cliff faces.1
In the central portion of the crevasse, near the three mile tall statues of Baba Yaga known as Artrosa, a series of plateaux cross the canyon's floor, creating a series of spectacular waterfalls. Thirty miles south of Artrosa, the forest of Hoofwood spreads over the cliffs and down to the floor of the crevasse, and the centaurs of the woods have carved trails allowing them to access the Myrfrus.1
South of the Hoofwood, the Myrfrus pours over a series of cliffs, upon which nest thousands of bloodhawks, eagles, and other large raptors who hunt the salmon of the river. South of the falls, the Myrfrus spreads out to cover a small plain, creating the massive, circular Lake Pirstjoi, from which rises the island known as Zvartjan. South of Lake Pirstjoi, the crevasse is bridged by the broken arch of Daruthrost.1 The crevasse continues further to the south, past the ruined town of Zradnirras, but ends before the Myrfrus empties into the Castrovin Sea at the port city of Mirnbay.2
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