Talk:My Little Pony Equestria Girls: Rainbow Rocks/@comment-24864975-20150202014750/@comment-10390252-20150323145558

We don't know what the Canterlot High end of the Mirror of Worlds was before it was included in the plinth of the statue (probably only around a century ago).

My headcanon is that it was originally a mirror too and had been owned by a succession of crazy European nobles and wannabe-wizards. It's quite possible that, if they checked, the girls would have found that Adagio, Sonata and Aria pop up in different places throughout history, always staying close to the human world terminal of the Mirror in the hope that they might be able to go home. They'd missed every opportunity because of the security under which it was always kept.

What happened? Maybe around the time the mirror came to America (maybe with the first Pilgrim settlers), the Dazzlings lost track of the mirror. They could trace its general location by the fact it eminates Equestrian magic whilst open but not find its specific location. So they took to hanging around Canterlot County and trying to somehow zero onto the mirror's location.