
And the FORTRESS they built here
has never been overcome.
Game of Thrones Season 4, Episode 5

I'd call it a
"Fortress of Solitude for babies."
The Big Bang Theory Season 10, Episode 6

Welcome to my FORTRESS of solitude.
The Big Bang Theory Season 8, Episode 7

We are about to enter Atzel's FORTRESS.
The Big Bang Theory Season 2, Episode 3

...I will be enjoying a blissful evening
in my personal Fortress of Solitude.
The Big Bang Theory Season 2, Episode 21