The Catryn Sea Crater is the inland depression that was once the mighty inland Greyfoam Sea that straddled the central and southern heartlands of the Steel Realms. It became the crater, and new home of the Ducateon within its walls and floor after the cataclysm that was the event in CY 5656 known as the Befoulment of the Gloaming, and was renamed after the Ducateon explorer Khat-Ryn, though is now pronounced “Catryn”. Anumha Falls still spills into its basin. It refers to the geological feature, though the area name is the renamed Ducateon ‘kingdom’ of Rockholme. The Gunhild Rise in the west carries water up into the The Torgrimson River, which marks the divide between the Central Heartlands and South Heartlands.