Manual:$wgLocalInterwikis

Details
Array for multiple $wgLocalInterwiki values, in case there are several interwiki prefixes that point to the current wiki. If $wgLocalInterwiki is set, its value is prepended to this array, for backwards compatibility.

Note, recent changes feeds use only the first entry in this array (or $wgLocalInterwiki, if it is set). See $wgRCFeeds.