Grrl Power #553 – Now that is a big door
Everyone who has a secure location is probably going to claim that it's one of the most secure ones in the world. It's marketing. Just like everyone's waffles or cheese blintzes or street tacos are World Famous. But in most cases, it's fairly unlikely people in Zambia are all a buzz about Jose's Street Tacos food truck in Reno.
But in this case, the fact that this location is 1000 meters down does probably place it in the top 20 of secure locations in the world. Really, when it was built back in the day, there weren't internet billionaires who could afford recreational deep sea submersibles on a whim either. It was probably top 3 before the someone invented the bathysphere. Unless you happened to be "creature from the black lagoon adjacent," or any other race that doesn't need to breath, isn't bothered by 100 atmospheres of pressure, aren't exceedingly delicious to a large variety of fish, and know where it is in the first place. Of course there are normally internal defenses in that first chamber as well. Like walls of force that randomly smack you off that no-railings walkway into the spike pit.
BTW I know a moon pool wouldn't work at 1000 meters deep unless that room was pressurized, which it obviously isn't, but, you know, magic. Though it would actually add a level of security if anyone who wanted to break in to your vault had to spend 18 hours decompressing afterwards.
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