Re:Secret doorway in UK Parliament leads to historical treas...
by EvilGrin on Wednesday February 26, 2020 @11:44AM
(#22424640)
If this was in England it may of been an extended priest hole to hide Catholic Priests after the reformation. If there was an entire chapel hidden away it may of been for said priest to conduct mass for the Catholic household in secret.
https://en.wikipedia.org/wiki/Priest_hole