I replayed Portal 1 after over 10 years and finished it in roughly 2,5 hours (+- 10 minutes, didn't check the time precisely). I don't remember it as THAT short!

Captain Johnathan M. Quirk

Yeah, if you think about it, the game can be cleanly broken up into 21 segments.

Captain Johnathan M. Quirk

Each test chamber, the escape sequence, and the boss fight.

Jan 26

It's a great game for speedrun material, and the shortness makes it more replayable to hone your Portal skills. At least for me.

Commando Booce

It's way, waaay shorter if you try and speedrun it. afaik you can beat it in under 10 minutes