Check out an Easter Egg spotted on the set of The Flash which features various cities time zones.
We see mention of Bludhaven, a home to Nightwing; Midway City, a home to Hawkman and Hawkgirl – both of whom will be appearing in DC’s Legends Of Tomorrow; Starling City, home to Arrow’s Oliver Queen; Central City, home to The Flash; Coast City, home to Green Lantern (which has been teased before), and we also see Opal city, the home of Starman.
It’s interesting to note that the two most wel-known cities in the DC univers are not listed with Gotham City (Batman) and Metropolis (Superman), which are most likely off limits to The Flash and Arrow, but that may change if the CBS Supergirl TV series ever connects with them.