Here it comes.

Looks like SCP facility

actually it's a long ass train that goes around the world after we f**ked up our enviroment to the point where everything froze

aka the snowpiercer

Looks like Backrooms level 1

So you know how the Snowpiercer is REALLY long, right?
SO basically, they built a sort of metro under the rooms to allow quicker transport.

So it's basically Level 1 of the Backrooms

yeah except there's no entities coming for your ass
except the breakmen
if you're a tailie that managed to get to the thing somehow