The Evacuated Zone was an area of London that was evacuated in the 1970s after dinosaurs began appearing, brought through time eddys by Whitaker as a part of Operation Golden Age. Eight million people had to be relocated and the government moved to Harrogate. The zone became redundant when the dinosaurs stopped appearing, Whitaker and his co-conspirator Sir Charles Grover having been sent into the past. (TV: Invasion of the Dinosaurs)
The Brigadier's map of the Evacuated Zone with "red pins for tyrannosaurus, blue for triceratops, green for the stegosaurus and pink for your actual pterodactyl." (TV: Invasion of the Dinosaurs)