Secret door

A secret door (or hidden door) is a door that appears to be an ordinary part of the wall, and can only be found by using the Search skill or using the spell Detect Secret Doors or True Seeing, and can also be detected by having a high Spot skill (an on-screen hint will pop up when nearby). Usually placed in spots ranging from completely obvious to absolutely surprising, secret doors are usually little more than a section of the wall that can be moved. There are also some secret doors that cannot be searched for or use Detect Secret Doors on; instead, a lever is hidden nearby that you use instead to open it, similar to opening regular doors.