Make minecraft world indestructible?

I want to build a Minecraft PvP arena, but the world has to be indestructible. So you can't mine anything but you should still be able to build. Can anyone tell me any order or anything? I also don't want to install or download anything.

Adventure mode?

Either you give the advent door fashion to the player or the effect paralysis.

Let the world run on a spigot server.

There you install the plugins WorldGuard and WorldEdit.

Then you can mark certain regions in your world and define the rights in each of them.

https://dev.bukkit.org/...worldguard should work if you do it on a server.

I wrote that I don't want to install anything.

I wrote that I don't want to install anything.

Oops