The final 13 episodes, combined series 4 and 5, were actually shot at various locations within the Republic of Ireland, mostly around the Dublin-Wicklow area, some with none to major digital set dressing enhancement. The city wall map in the office, in Series 4 and 5, is actually Dublin City, turned upside down.
The most accurately portrayed extinct animals in the entire series with only a few minor errors are the; Ammonite - (Episode 1.1) Protosolpuga - (Episode 1.2) Dodo (Episode 1.4) Pteranodon - (Episode 1.5) Deinonychus - (Episode 2.1) Smilodon - (Episode 2.3) Eoarthropleura - (Episode 2.5) Columbian Mammoth - (Episode 2.6) Diictodon - (Episode 3.3) Embolotherium - (Episode 3.9) Australopithecus - (Episode 3.10) Liopleurodon - (Episode 5.2) Tyrannosaurus - (Episode 5.5)
A total of seven actors who have played major characters on 'Primeval' (Lucy Brown, James Murray, Andrew-Lee Potts, Juliet Aubrey, Ciaran McMenamin, Laila Rouass and Anton Lesser) have also appeared in the popular TV series 'Midsomer Murders'.
Ben Miller (James Lester), Hannah Spearritt (Abby Maitland) & James Murray (Stephen Hart) all appeared on episode 2.6, A Dash of Sunshine (2013) of Death in Paradise (2011) as DI Richard Poole, Lily Shaw & Ronnie Stuart respectively.
Wellington Zoo scenes were filmed at London Zoo and Whipsnade Zoo.