A high-density media storage system. One embodiment of the high-density media storage system may comprises a plurality of storage libraries, each configured to store data cartridges in a horizontal orientation in high-density relation to one another. Such system also comprises a cartridge-handling apparatus having a drive assembly, the drive assembly moving the cartridge-handling apparatus through a displacement path through the plurality of storage libraries. The system further comprises an operational envelope provided at one end of the displacement path in one of the plurality of storage libraries, the operational envelope sized to receive only the drive assembly of the cartridge-handling apparatus when the cartridge-handling apparatus is positioned at the one end of the displacement path.