A reliquary was a religious storage place where relics and artifacts were kept.
The Vulcan monastery at P'Jem had a reliquary in its catacombs. According to the Vulcan elder no visitors were allowed at the reliquary – this would be blasphemy. Only members of the high order were allowed inside.
The reliquary at the monastery featured several shelves filled with vases, statues, sculptures, and other artifacts. Behind a tapestry, it also featured a shiny round-shaped metal door which marked the entrance to the secret listening post operated by the Vulcans. (ENT: "The Andorian Incident")
The reliquary in "The Andorian Incident" was filmed at Paramount Stage 9. (Call sheets)