What is every location in main series Pokemon that is accessible at one point, but not accessible at a later point?

Jul. 20, 2021

Like Team Flare HQ in Geosenge Town, or Lusamine’s room in Pokemon Sun/Moon.

Include places that don’t actually change the name of the location your in, like Lusamine’s room, but are still different areas.

Pleaselog inorregisterto add a comment.

Mirage Tower (Emerald) will collapse once you reach the pinnacle and select a fossil of either Lileep or Anorith. This one I speak from experience and know for a fact you can’t go back to.I also believe the Distortion World (Platinum) is impossible to return to. But don’t hold that to me. I’ve never tried.commented Jul 26 by Ætherborn Rogue

Marine Cave and Terra Cave become inaccessible after you catch or defeat the Pokemon inside it. The Distortion World has 2 parts, and 1 of them becomes inaccessible when you enter Sendoff Spring.commented Jul 26 by sumwun

Please comment if I missed any.

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