In 2007, when Portal first came out, I became obsessed with it and would play it all the way through every day. I even got into making maps for the game.

I participated in a forum with other Portal map makers, and I still have some of the files. I also have a working version of Portal that can run them.

I recently came across the best map I ever made, which I called Door Tunnel. It was buried deep in an ancient hard drive that I hadn’t checked in a long time.

I managed to get it loaded after a bit of wrangling, and I made a video of what it looks like to play it.