<P> The BBC has also broadcast several documentaries alongside the show, examining the making of the show and showcasing a selection of' out - takes' from the filming . </P> <P> The idea for the show occurred to actor James Corden during a wedding reception, and he then developed the idea with co-writer Ruth Jones, whom he had met during the filming of ITV drama Fat Friends . Corden claims to have been inspired by the story of his own real life best friend Gavin, who met his wife over the phone at work, and arranged to meet . They presented it to the BBC as a one - off play, but the BBC instead asked for a full series . The roles of Gavin and Stacey were cast through an auditioning process, but were almost immediately given to Mathew Horne and Joanna Page on the strength of their chemistry together . The roles of Nessa and Smithy were written by Corden and Jones for themselves . Some roles were written with certain actors in mind; Uncle Bryn was written specifically for Rob Brydon, who had been to school with Jones, whilst Pam was written specifically for Alison Steadman, who had also worked on Fat Friends . Jones had worked with Julia Davis in her sitcom Nighty Night, and the role of Dawn was written with her in mind . Additionally, Corden had appeared with Adrian Scarborough in the Alan Bennett - penned play and film, The History Boys, which led to him being cast in the role of Pete . An audition process was used to cast the roles of Mick and Gwen, whilst the roles of Gavin's friends were given to Corden's co-stars in The History Boys . </P> <P> Although the programme is set in Billericay, Essex, and Barry, Vale of Glamorgan, the three series were shot largely in Cardiff (which acted as the city itself but also as parts of Billericay), and also in Barry itself and the surrounding area, including Dinas Powys, Sully and Penarth . The show's popularity has been credited with boosting the tourist trade to Barry and its popular seafront of Barry Island, through visitors wishing to visit the various filming locations . Gavin's house was set in Billericay but was actually filmed on location in Laburnam Way, Dinas Powys in Wales . The opening episode features location shooting in Leicester Square in London which was filmed in 2006 . </P> <P> After the debut of the show on BBC Three, a second series was soon commissioned . Speaking about the second series, Corden said "It's the show that we wanted to make . If people like it, they like it: if they don't, they don't . That's a nice feeling, that's quite freeing...There's more of a journey and more of a story . We hope the viewers will feel like they've been taken on a little trip by it", while Jones said "Series one had a very specific storyline to it, boy meets girl and it ends in a wedding . We don't have the same type of storyline in the second series . It's now girl lives with boy's parents in Essex and the joys that might entail ." </P>

Where was gavin and stacey filmed in wales