The Refugium was a dream world. It contained areas of forest or tundra that existed between areas dominated by Jaghut ice in the ages before or not long after the Ritual of Tellann. It maintained the lush habitat that the original Imass occupied. Within the Refugium, many creatures and vegetation that existed in the time of mortal Imass also lived, though they might be extinct everywhere else, such as emlava and ay.
The Ritual of Tellann did not exist within the Refugium; T'lan Imass who entered regained their flesh and returned to a mortal state. Likewise, ghosts who entered also became mortal. Prior to events at the end of Reaper's Gale, if a T'lan Imass or ghost were to depart the Refugium, however, they would return to their true state.
The Refugium was openly accessible from Verdith'anath without any distinguishable border other than where the grass began growing. Additionally, the Refugium had a chamber containing 12 gates to other warrens, including Kurald Galain and Starvald Demelain.
The Refugium existed for hundreds of thousands of years, but as the power of the Bonecaster sealing the gate to Starvald Demelain faded, so too the Refugium began to die. As the power of the ritual failed, the Bentract spirits, T'lan Imass, and Hedge became mortal in truth.
An Azath House known as Kettle House was created inside the Refugium, rooting the realm and preventing it from dying while also sealing all 12 gates. However it was an abomination in the eyes of nature since it was doomed to go in circles and never change.
The Refugium was destroyed when the Eleint broke through the gate to Starvald Demelain, destroying Kettle House.