# Detect when players cross Z coordinate 1.19

I've seen similar questions, but their commands seem to be outdated. Although I don't have much experience with location-based command blocks, so forgive me if I am wrong.

I am trying to execute a command if a player crosses a certain z-coordinate.

Something like: `/execute if entity @a[z=-369] run say @a`.

I.e., if a player crosses into z=-369, execute the command block.

I figured it out.

`/execute as @a at @s if entity @p[z=-368.5] run tp @s ~ ~ -369.5 `

This command triggers if a player crosses into z=-368.5 and teleports them to -369.5

The `as @a at @s` means that the command is executed from the player's position, not the command block's.

### Edit

The current barrier is very easy to break out of with a boat. ExpertCoder14 mentioned how to improve upon the command:

``````/execute as @a at @s unless entity @p[z=-369.5] run tp @s ~ ~ -369.5
``````
• Use `@s[z=-368.5]` instead of `@p[...]`. It will have the same end result, but it should be faster. Also, this can be very easily cheesable if you care about that, for example with a boat. Jul 23, 2022 at 18:15
• Yes I realized yesterday how easy it is to escape. Is it possible to fix this by making a `if not`? Something like `if not entity @s[z=-369.5] run tp @s ~ ~ -369.5` Jul 25, 2022 at 4:09
• You could store the coordinates into a scoreboard and use the `if score matches x..y` and so something like `if score @s Z matches -365..` Jul 25, 2022 at 14:44
• @VinceKaj `if not` is `unless`. `/execute unless entity @s[...]` Aug 6, 2022 at 21:40