I'd call it a
"Fortress of Solitude for babies."
The Big Bang Theory Season 10, Episode 6
We are about to enter Atzel's FORTRESS.
The Big Bang Theory Season 2, Episode 3
The greatest FORTRESS ever built.
Game of Thrones Season 2, Episode 7
Casterly Rock
is an impregnable FORTRESS.
Game of Thrones Season 7, Episode 3
And we need
every FORTRESS we have
Game of Thrones Season 7, Episode 1