User blog comment:Kacj321/Entire Tamriel Landmass built into Skyrim/@comment-4623022-20111122180414

I think these are foreshadows for DLC, that gate would of had a door the was "required key" on it. and plus i cant think of any other reason they would put them in except for place holders for the Creation engine terrain's. plus i couldn't think of any other thing they could use for DLC.