The Soulsand Valley's naturally generated bone structures can generate at the top of the nether resulting in an accessible open path to the nether roof.
Example
Seed: -2200534683779441623
Teleport Command: /execute in minecraft:the_nether run tp @s 10314.19 129.43 899.25 358.49 26.39
NOTE: In screenshot attached, the bone blocks have been broken to visualize the available path.
Thank you for your report!
We're actually already tracking this issue in MC-173199, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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