In 2012, at least three Astros fans wandered off from an outdoor carnival, slipped through a gap in a fence, and found themselves smack in the middle of the abandoned Astrodome.

Houston's MLB team hadn't played there since 1999, and it was used only sparingly before being fully closed in 2009. The guys found some of the hallway lights on in the building and proceeded on an adventure that took them through the spooky confines of the old stadium that was once also home to the NFL's Houston Oilers.

Three days ago, one of the guys in that group uploaded photos from their adventure onto Imgur.

One of the first areas the guys discovered was the Astros' locker room. Although the locker names had been removed, the decoration in the room made it clear this was where the home team set up shop:

"We were NOT in there to vandalize, steal, or damage any property," the original poster writes. "Just there to see how the ol' dome was doing! Also, I do not know the current condition of the Astrodome, and even if it were to be in the same condition as it was when we checked it out, I would NOT recommend and do not condone trespassing on private property."

The guys then made it out to the bleachers, where the Astrodome's seats were still intact. Judging by the padded seating, they were likely on the lower level close to the field:

The guys made it up into the higher reaches of the stadium, exploring the old Astrodome suites and finding the media rooms near the top. One of the men manned the stadium's scoreboard control and found a key that turned on everything but the Jumbotron.

Finally, as if this was the only way things could have worked out, the guys found their way to the roof of the Astrodome (which could be converted to a "massive indoor park within the stadium, with spaces for exercise and biking trails and indoor rock climbing," according to an AP report).

. In fact, they didn't even have to look that hard: According to the caption, the first door they tried revealed a ladder leading straight to the top.

The moral of the story: Never underestimate how easy it is to walk into a multi-million-dollar facility unobstructed, and never assume that you can't do whatever the heck you please, turning that facility into your own private, albeit derelict, playground.

Oh, and don't trespass. But if you do, take pics or it didn't happen.

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