I forgot where this area is could somebody please help me :)

[palmerrulzah]

Hey guys i was at my mates house a while back, watching him play Skyrim, and i remember him going into some room in a dungeon i think where he walked into the middle of the room, all of these gates sprung up around him, the floor opened up and he fell deep to the bottom of the dungeon.the gates were dwarven crafted i'm pretty sure

does anyone know where this place is eg the name of the dungeon? or the quest to get in there?

help would be greatly appreciated ive been on my own hunting all over skyrim for it

 

[Grey Fox]

That would be Kagrenzel. North of Riften and NE of Shor's Watchtower.