The Molten Plain of Mount Zera

While the Frost Giants and the Fire Giants are both sworn enemies of the Aesir, and when the time of Ragnarok comes it is said they shall ally their forces to destroy the Aesir, that doesn't mean that they are allies by any means. While for the most part, their preferred environments keep them apart, that isn't always the case, and the volcanoes of the Norse lands can bring these two forces quite close, and that can certainly lead to conflict. Some say that Odin seeks to manipulate such conflict when he can, so as to delay any alliance of the forces of Jotunheim and the forces of Muspelheim. Being a volcano, the Fire Giants took up residence in the area, and took advantage of the volcano's fire for their forges. The land around the volcano though is quite cold, and bitterly so in the winters, the sort of place that the Frost Giants find quite comfortable. Legend has it that the two groups traded, and indeed prospered together for hundreds of years. At first in small ways, but over time the Fire Giants built a small city in the volcano, and the Frost Giants built a string of forts around along what is now the Molten Plain, and actually began to mine the region, finding precious metals and gems in the region. To hear the Frost Giants tell the tale, the trouble came when the Fire Giants grew envious of the wealth that the Frost Giants were drawing from the ground. When merchants couldn't agree to a fair trade of gems and jewels that the Frost Giants had crafted, the Fire Giants attacked and killed the Frost Giants, and took their goods as plunder. This spiraled out of control, and became a war, drawing in Frost Giants from many nearby tribes. The Fire Giants were not able to recruit allies as easily, but they had a great defensive advantage given that they lived in the volcano, and the lava was as dangerous as water to the Fire Giants. Yes, they could technically drown in the Lava, but the heat was no danger to them. But the Frost Giants had managed to recruit mages from the realm of Svartalfheim, Dark Elves who wove spells to protect the Frost Giants from the heat of the Volcano. When the Fire Giants realized that they were not safe in the volcano, they called upon their Lord Surtur for succor.  The Lord of the Fire Giants declared that fortress of Mount Zera would never be be taken by Frost Giants. The Frost Giants and their Dark Elf allies massed and advanced on the fortress, but as they neared the gates to the fortress, the volcano erupted, crashing away about a quarter of the side of the mountain, and drowning the plain for miles in lava.  The eruption blasted ash and debris miles into the sky, and plunged the area into a darkness that some thought was the start of Fimbulwinter.  It isn't clear if any survived the eruption.  It is said that a handful of the Dark Elves did, escaping using teleportation, or plan shifting, but no Frost Giants made it to the fortress.  Surtur had ensured that, although the Fire Giants who were there may have been hoping for a less destructive miracle...

Geography

A plain about 10 miles long, and two to 5 miles wide, the Molten Plain begins at the foot of the missing section of the caldera around Mount Zera.

History

Part of a Nordic volcanic mountain range, Mount Zera is said to have been home to a city of Fire Giants long ago.