20 Awesome DC TV Easter Eggs You Probably Missed
3. The Speed Force (And Cannon) Visions (The Flash)
Be it travelling through time or dimensions, The Flash has made use of these speed tunnels (the Force and the Cannon) to drop in a number of great Easter eggs. During the Speed Force segment of the Season 1 finale, we see a young Barry moving in with the West family, Caitlin Snow as Killer Frost (which paid off in the last couple of episodes), the Flash museum, and most intriguingly Barry Allen locked-up in Iron Heights prison - both signs of things to come?
In Welcome to Earth-2 (what else?), Barry travels through the speed cannon and we see: an alternate version of Green Arrow, possibly Connor Hawke or an old Oliver Queen (both of whom will be on Legends of Tomorrow); Jonah Hex (Legends again); Grodd; John Wesley Shipp's original Flash (a nod to the Jay Garrick reveal); the ring of the Legion of Super-Heroes (probably Legends); and, of course, Supergirl, which crossed over with The Flash not long after this.