They do it with seats that magically disappear. Seriously. The O2 uses a system of retractable seating. For basketball, the arena holds 18,000. For boxing, it’s 16,000. But for music, they pull out the floor seats like a giant game of Tetris.
If you take away the seats entirely—like for a standing “general admission” pit—the capacity actually drops to about 17,500. Why? Because people take up more space when they’re flailing their arms to "Sweet Caroline."
And here’s a mind-bender: The O2 is so big that its internal volume could fit 11 Olympic-sized swimming pools. That’s 11 pools worth of screaming fans, dropped nachos, and the occasional glow stick that rolls under someone’s shoe.
The Toilet Capacity Crisis
Naturally, with 20,000 humans comes a toilet crisis of biblical proportions. The arena has over 500 toilets. That sounds like a lot until you realize that during a 15-minute intermission, 20,000 people suddenly need to pee.
That means about 40 people per toilet. So unless you’ve mastered the "ninja queue jump" or have a bladder of steel, you’re looking at a 15-minute wait for a 30-second relief.
Pro tip: Always go to the toilets on the upper level. They’re always emptier because everyone thinks climbing stairs is too much effort. It’s like a secret society of peeing efficiency.
Oxygen Chart For Tanks – Gauge Charts – UTVRT
