World appears twice on World Map

Create a backup of your save game in case something goes wrong

First you need to do some preparations in the game to make editing with S4 Studio easier.

Start your game and go to map view.

Identify which case applies to you.

Go to step 8 for cases 3&4

Choose which of the two worlds you want to keep. It’s easy to decide in case 2 as worlds without lots are useless.

If both worlds have lots, choose the one that you haven’t played with or simply the last world.

Switch to the world and change the description (if present) to Delete. If the field is missing, proceed to the next step.

Go to step 8 for case 2

Evict all the households you want to keep from the world. This will allow you to place them again later on.

Premade households appear in both worlds and because of this appear twice in the household manager. You should remove the version in the world you want to delete.

Rename the family in the world to be able to easily find and delete them in the household manager.

Rename all the lots in the world to Delete.

Change to the household manager and delete all the households that you renamed earlier.

Save your game with save as under a new name. There’s also no harm in making two backups or making a copy of your saves folder.

Save files are just renamed package files so you can open them in S4 Studio.

Start S4 Studio and click on My Projects then navigate to your saves folder.

Sort by modified date and choose the newest file. Make sure to choose Sims 4 Save as file type so that the files become visible.

Choose Save Game Data on the left hand side and search for neighborhoods on the right (there are two so make sure to pick the first one).

Click on Edit Items.

A window with all neighborhoods will appear. Search for the world you want to delete.

The order gives a clue which one it is but since you changed the description you can be sure it’s the correct one (it will be empty if you weren’t able to enter one)

Click on the world you want to delete and choose Remove. Then click on Save to save your changes.

Delete both worlds for case 3 and the only world for case 4.

Click on save again to overwrite your save game (or choose File – Save as to save it under a new name)

At this point you are finished for cases 2-4. Start your game. New worlds will be created if you removed all of them. If it didn’t work, try again with your backup but make sure to create a new backup.

For case 1 you will also need to delete all the data from the lots.

On the right hand side, scroll all the way to the bottom until you find zones. Click on Edit items again.

Filter the list by Delete to see all the lots you need to remove. These lots are orphans now as you removed the world they belonged to.

For each of this lots you also need to delete the corresponding Zone Object Data. To do this choose the first entry and scroll on the right hand side all the way to the bottom until you see zone_id

Copy the ID to your clipboard.

On the main window, copy the ID into the filter field and filter by it.

You will see 1-3 entries that you all need to delete. To do so, select them all and click on Delete or use the Delete button on your keyboard.

In the appearing window you need to select all entries again and click OK to confirm that you want to delete them.

The entries will not disappear from the list right away although they are deleted. You can check on it by clicking on the filter button again.

Repeat this for every entry in step 14

Once you deleted all the corresponding Zone Object Data, you also need to delete the lots (zones) themselves.

Select all the lots and click Remove and then click on Save again to save everything.

Save everything again into the package file.

Test your game if the world is now gone.

If the game now crashes, you forgot to remove something Try again on your backup and make sure that you don’t forget anything.