
...um, I embarked
on a RAILROAD journey of healing...
The Big Bang Theory Season 8, Episode 1

I'm gonna be working on the RAILROAD
all the livelong day.
The Big Bang Theory Season 10, Episode 15

In 1944, the Pacific Railroad
built number 6131,
The Big Bang Theory Season 7, Episode 15

You'd have to drive a RAILROAD spike into
his brain for me to beat him at checkers.
The Big Bang Theory Season 2, Episode 11

Well, Sheldon was going on and on
about time zones and RAILROAD schedules,
The Big Bang Theory Season 9, Episode 16