The Loth'Na Caverns is a large cave with an inner sanctum in the middle. The center of Inner Loth'Na is a tall hill with stones jutting out the area and Nirncrux veins located throughout the area. There is a small river that runs through the southern end of the cave, and it continues into the Druadach Mountains and the rest of Craglorn. Loth'Na is located north of the ruins of Skyreach, which was originally a city built by the Nedes of Hammerfell. The outer ruins of Skyreach are located on the mountaintops of Upper Craglorn, with bridges connecting them to the higher roads in Craglorn. Located in Loth'Na is the Skyreach Temple, which makes sense considering the caves proximity to Skyreach.
During the Interregnum in 2E 582, the Scaled Court had worshipped the Serpent and considered him a powerful being. The Scaled Court began to arose throughout Upper Craglorn, making a pact with the Iron Orcs of the region. Regent Cassipia of the Scaled Court desired to gain the same powers as the Serpent, posing a great threat to the denizens of Craglorn. With the help of a traveler known as the Vestige, Regent Cassipia was able to destroy the Mantikora and defeat the Nirncrux-infused Iron Orcs. Cassipia and Little Leaf, her partner in crime, traveled to the Skyreach Temple in Loth'Na Caverns to complete the process but was interrupted by the Vestige, the Thief, and Titus Valerius. The Vestige defeated both the Exalted Viper and Little Leaf's spirit, saving both Craglorn and the rest of Tamriel from the wrath of the Exalted Viper.
During the Imperial Simulacrum in 3E 397, the Nords of Skyrim under General Duvais, besieged the city of Dragonstar and taken control of the Eastern side of Dragonstar, oppressing the denizens of the city. Duvais and his men discovered a powerful crystal deep within Loth'Na and utilized it to enhance their power and kill pilgrims coming to Loth'Na. Porliss Caith of Dragonstar tasked an estranged warrior to eliminate Duvais in Loth'Na and to secure the area for pilgrims to come and worship as they please. The crystal that Duvais used had killed several pilgrims, causing their spirits to remain on Nirn. The same warrior aided the spirits and brought them to Aetherius.