London, May 29 : The 'hell' door which Austrian incest dad Josef Fritzl used to trap his daughter and their kids inside the dungeon weighs a massive 660lb, it has emerged.
The 73-year-old fiend sprayed concrete on the steel frame so that his daughter, Elisabeth and the seven children she bore him, could never shift the heavy gate, reports the Mirror.
Fritzl lured Elisabeth, 42, into the cellar in Amstetten, Austria, in 1984 by asking her to help carry the door downstairs, before trapping her.
Inside the cellar evil Fritzl repeatedly raped his daughter for 24 years and fathered seven kids with her.
The brute's activities came to light after Kerstin, one of Fritzl's incest child, was hospitalized.
Now, the cellar family is considering moving to Britain to start a new life with new identities.