1. A system, comprising: one or more hardware processors; and one or more memories storing instructions that, when executed by the one or more hardware processors, cause the one or more hardware processors to: select a first representative media item that defines a first region, wherein a size of the first region depends at least in part on a size of a reduced resolution image associated with the first representative media item; determine a first set of media items that belong to the first region; select a second representative media item that does not belong to the first region and that defines a second region; determine a second set of media items that belong to the second region; and send the reduced resolution image associated with the first representative media item and a reduced resolution image associated with the second representative media item to be displayed; wherein the reduced resolution image associated with the first representative media item and the reduced resolution image associated with the second representative media item are displayed on a map in a non-overlapping fashion.