Delirium Archive

The Delirium Archive was an asteroid-based museum visited by The Doctor and Amy in the 171st century. It was described by The Doctor as the biggest museum in the universe and the final resting place of the Headless Monks. The Doctor regularly visited the museum, as a way to keep score. This was known by River Song, and she exploited it to summon him, carving a message in High Gallifreyan into the Home Box of the Byzantium, knowing it would turn up in the archive. (DW: The Time of Angels)