The Ring of Storms is a region of Xen'drik, located in the mountains to the east. It's a valley surrounded by a ring of cliffs and mountains, and the area is constantly buffeted by storms.
The region was once the home of the city state of the Qabalrin, who lived there for thousands of years. Even the Cul'sir Dominion had a healthy fear of these elves, who were the foremost necromancers in the world at the time. Their rule over the region was ended roughly 40,000 years ago, when an enormous Siberys dragonshard, nicknamed the Heart of Siberys, fell on the city. The blast destroyed the city and morphed the surrounding region, creating what is now known as the Ring of Storms.