Found a door in the upstairs of this cabin-like building that has the "open door" option, but the door won't open. You can also "close" it after, with nothing happening. Door doesn't move, can't walk through it. Not exactly sure where this cabin is since there is no map (or haven't found one yet). Here's a link to the picture of said cabin, and the door.

http://steamcommunity.com/sharedfiles/filedetails/?id=204706850 - cabin
http://steamcommunity.com/sharedfiles/filedetails/?id=204706838 - door