Manual:Merging a wiki into another wiki

Merging a wiki into another wiki, i.e. copying all the content from a source wiki into a target wiki (e.g. if you decide that you really only need one wiki rather than two separate wikis), can be done by manual or automatic means.

Methods
Either way, you're going to follow these steps:
 * Set $wgExportAllowAll to true.
 * Use Special:Export to export everything from your source wiki.
 * Use Special:Import to import everything into your target wiki.

Manual

 * Download every file individually from your source wiki.
 * Upload each of these files individually to your target wiki with a suitable description.

Automatic

 * Write a bot to download all the files and their descriptions from the source wiki, saving the descriptions to a text file.
 * Use Manual:ImportImages.php to import files with their descriptions.

You're done!