Building a Block-Jump-Proof Wall

[xpeterc1]

put a glass wall or something just behind the air pocket, dont fill it in, it stops blocks from being built there so people cant wall hop over it, and a person cant fit in that 2 airpocket since it's really 1 and a half block.

 

[gtastuntdude]

You could always do what we did with Underdeep :3

Have a dome with a region over it

Or submerge your town with water....

 

[Shenorai]

That's very true. And with only a couple entrances/exits, Underdeep was even safer than Neverast was back in the day.