Manual:$wgUploadDirectory

Server URLs and file paths: $wgUploadDirectory
The file system path of the upload directory.
Introduced in version:pre 1.1.0
Removed in version:still in use
Allowed values:(absolute path)
Default value:"{$IP }/images" (1.8+)
"{$IP }/upload" (pre 1.1.0 - 1.7)
(Note: The default value of this variable depends on other variables, such as the values set in Setup.php , after LocalSettings.php is executed)

Details edit

The file system path of the folder where uploaded files will be stored.

If this variable is changed, you may need to update $wgUploadPath accordingly.

This location needs to be writable by the web server. See Manual:Configuring file uploads#Check directory security.

By default, uploaded files are actually stored in subfolders of $wgUploadDirectory. See Manual:Configuring file uploads#Upload directory for information, and how to disable this behavior.

There are other variables which are defined relative to this one. If you redefine this in your LocalSettings.php then all dependent variables including $wgUploadPath will need redefining also. If both these settings are not coherent the files will be uploaded to different folder ($wgUploadDirectory) than from where MediaWiki will try to retrieve it for viewing ($wgUploadPath)!

See also edit