The Circle of Visions was a circular chain of volcanic islands and coastline locations on the Sith World of Upekzar that ran from the planet's equatorial regions down to its south pole. The ancient Sith of the Sith Empire who colonized the planet confined their settlements to five distinct locations along the Circle of Visions, each of which hosted an extensive volcanic cave system home to colonies of rhak-skuri.
The Circle of Visions was the name applied to a circular chain of isolated islands and coastline locations found on the Sith World of Upekzar. Stretching across the planet's southern hemisphere from its equatorial regions down to its south pole, the Circle of Visions was notable for its high concentration of volcanos and associated lava cave systems formed from retreating magma. The latter cave networks often hosted colonies of rhak-skuri, a subspecies of diplura endemic to Upekzar who hunted by means of a pheromone known to cause nightmare-like hallucinations in certain humanoid species.
The ancient Sith of the Sith Empire who settled the planet focused their colonization efforts on five main locations along the Circle of Visions. Here, abiding in settlements and cities that dwelt in the shadows of the Circle's volcanos, the Sith conducted ritualistic Mysteries in nearby cave systems, unprotected from the pheromones of the rhak-skuri. Though each settlement hosted rites related to a distinct aspect of the dark side and could be found in locations as diverse as the south pole and the equatorial heartlands, the planet's largest city lay close to the expansive cave system associated with the High Rites.
The Circle of Visions was first discovered by the ancient Sith of the Sith Empire. During their initial explorations of Upekzar, the Sith discovered the Circle of Visions' volcanic cave systems and stumbled upon the native rhak-skuri, an insectoid subspecies of diplura who inhabited the volcanic caves along the Circle of Visions. These Sith explorers frequently experienced nightmare-like hallucinations mediated by means of the rhak-skuri's pheromones, and over time, the Sith residents of Upekzar came to develop and conduct a number of rituals of Sith magic and acolyte initiation ceremonies that involved protracted exposure to the creatures' pheromones.
The Sith restricted their colonization efforts to five major sites along the Circle of Visions, each of which hosted a settlement and cave system associated with a certain rite of their ritualistic Mysteries. The Cold Rites were conducted close at hand to Upekzar's frigid south pole, while the Rites of Fire were held in the equatorial regions of the planet. The most significant rituals, undertaken by only the most powerful Sith Force users on the planet, were the High Rites, held within an extensive cave system in one of Upekzar's more temperate locations. The planet's largest city lay some three kilometers away in the shadow of a dormant volcano.
In 44 ABY, during the Jedi Order's search for the Force entity Abeloth and the Sith Meditation Sphere known as Ship, Grand Master Luke Skywalker and a strike team of Jedi investigated the ruins of the ancient Sith city and the extensive cave system in which the Sith had performed their High Rites. While spelunking through the latter, Ben Skywalker, Vestara Khai, and Natua Wan discovered that as a result of the residual dark side energy generated by centuries of Sith rites, the rhak-skuri had mutated into two-meter-tall creatures that had evolved some degree of sentience. These creatures were able to recognize Khai as a Sith, telepathically communicate with her, and differentiate between light-sided and dark-sided Force users.
The Circle of Visions makes its sole Legends appearance in Fate of the Jedi: Ascension, and is only mentioned by name once in the novel's text despite serving as the setting of the Upekzar-based narrative section.