When referencing any of these listings, recall that *** by a point means that a footnote is provided at the end of the timeline, '-' means that an event succeeds everything above it, while a series of, '*'s mean that it is unknown which event occurred before the other. '-U-' means that this event is dated according to Ultimania, a flawed guide for Chrono Cross written in Japan that may nonetheless have some credibility.
Please note that the appearance of Chronopolis in 12000 B.C. and the contact with the Frozen Flame in 3000000 B.C. are arbitrary dates, created by the Chrono Compendium. Chrono Cross never specifically states when these events occurred; concerning Chronopolis, "ten thousand years" is both used to describe its displacement in the past and also its tenure of watching El Nido until 1020. The presence of icebergs in the war with Dinopolis suggest Chronopolis went back to a time not long after the Ice Age began to wane. The Frozen Flame contact was also merely described as happening three million years ago, but on such a large scale, it is only important to remember this figure.
From: Main Page