Physical Description
The sanatorium is located in the Pearlbow Wilderness, near the towering Dunrock Mountains, about a day and a half's journey from Rexxentrum. It consists of a number of tall, gothic buildings and towers. It is surrounded by a tall wrought-iron fence, with a main gate, ten feet high by eight feet wide with a curved top, and is heavily guarded, with Crownsguard in camouflaged uniforms posted at the gate. Within the fence is a grassy courtyard with with two fountains, some trees, and gardens.
The main structure is split between five major buildings, two of which are connected by hallways and the others of which are connected via outdoor stone pathways. Towers stand at the corners of the interior. The central building, where most patients are kept, is a large mansion with a multi-peaked roof, the peaks of which are topped with iron symbols. It was described as "European church-type architecture," but without any religious symbols.
There are two smaller mansion-like abodes on the premises, a general use stone building and tower to the northwest, and a much more extravagant tower on the northeast side which Trent Ikithon uses as a summer home. The northwest tower is used by the people who work at the sanatorium for research and lecture purposes. The northeast tower is wide, about eighty feet tall, and tapers toward the top. It houses a waiting area for visitors. A spiral stairway leads downward to a locked door, Trent Ikithon's arcane laboratory.
The Laboratory
The arcane laboratory holds multiple bookshelves and tables with glass vials and alchemical contraptions built from coiled copper. Against one wall are shelves with locked glass doors with unknown other materials. The room is high-ceilinged and lit by a single bright chandelier.
Uses
Ludinus Da'leth told the Mighty Nein that the sanatorium had many uses: patient recovery, the caretaking of those who could not take care of themselves, particularly those who were found challenging to treat due to their abilities. It also served as place of learning for those with learning challenges, and a location where the Cerberus Assembly could perform some of their research "without worrying about political challenges."
Ludinus stated that patients who were not admitted were free to leave. Some patients were there by choice and gave consent to be held there for a period. Other patients were kept because they were a danger to themselves or others, and were not free to leave.
Some of Caleb's training as a Volstrucker took place there.
While Ludinus's statements about treating patients with legitimate illnesses, mental or physical, is true, the sanatorium is also secretly used as a torture site for political prisoners. Dissidents and spies are sometimes sentenced to the sanatorium by Sydnock Truscan for this purpose.
Background
The building that now houses the sanatorium was constructed some time during or before the Marrow War. Known as the Archevault, it was used by the Empire as a jail for prisoners of war. The Cerberus Assembly came into possession of the Archvault and repurposed it as a sanatorium. It was renamed after its founder, the late Assembly member Lord Symon Vergesson.
" Whispers of War " (2x18)
Caleb tells Nott and Beau that when he broke after killing his parents, he went to an asylum for quite a number of years. He doesn't remember much of what happened to him there, but years later a woman, another patient, put her hands on him and took away the "clouds" and the fake memories that Trent Ikithon had implanted of Caleb's parents discussing treason. When he broke out, he killed a guard and took the amulet protecting him from being located.
" A Game of Names " (2x49)
Caleb shares part of his history with the rest of the group, saying only that a lot of big plans for him didn't go as planned, that he had a mental break of some sort, and that he ran away.
" Unwanted Reunions " (2x88)
The Mighty Nein are brought by Ludinus Da'leth to Trent's arcane laboratory beneath the Sanatorium to inspect the Luxon beacon being held there. Caleb tells the group he was held there for eleven years.
" Lingering Wounds " (2x89)
When Caleb asks Astrid how he got to the Sanatorium, she tells him that "we took you there" when he broke after setting his parents' home on fire. She says that it was for his own good and perhaps inadvertantly shows him the burn scars she presumably received from him when he was in that state.
" Sarsaparilla, Licorice, and Red Hot " (2x127)
After Caleb asks Astrid for amulets to protect against scrying, she gives him directions to a supposed cache of the amulets, which she refers to as "veilers," in one of the outer buildings at the Sanatorium. The Mighty Nein break into the sanatorium to acquire them, with Jester, Veth, and Caleb going inside on the main mission. The building proves to be both heavily guarded and included multiple arcane protections. They charm or kill the guards they encounter and reach the vault Astrid had told them about. It is guarded with a Wall of Force, and while Caleb does not have the spell slots to cast Disintegrate, Jester is able to bypass it with a Dimension Door.
Jester and Veth are able to acquire the amulets, but Trent Ikithon had been alerted to their presence and nearly prevents them from leaving.
" Cat and Mouse " (2x128)
Caleb is able to counter Trent's Counterspell, allowing Jester to teleport them off the grounds.
Artwork