The final activation hole looks pretty cosy in that little tower, doesn't it? Well, why don't you hop in there and keep it company?
How do I do that?
Press both standing buttons in rapid succession, then place a portal at the bottom of the 'tower' that holds the activation hole.
Shoot another portal on the ground near you, jump down into it, and move forward into the tower - after some unique dialogue, you'll be unceremoniously kicked out.
What is the unique dialogue?
"Through no fault of the Enrichment Center, you have managed to trap yourself in this room. An escape hatch will open in three... Two... One."
Guide help
This is the low-spoiler guide for "Breaking the puzzle" puzzle in Portal. Unlike in normal walkthrough, you get gradual hints on how to solve the puzzle. Click the big button below to see your first hint. If the hint contains a spoiler, you will be warned about it before clicking.
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