EastEnders turns 40: Discover 40 mind-blowing facts only true superfans know

Producers visited graveyards to help them come up with realistic East End names.

The name of the fictional location was created by mixing the first three letters of Walthamstow and last four of Stratford – the areas of London where creators Julia Smith and Tony Holland were born.

Before EastEnders launched, more people were seen for the role of Kathy Beale than any other part. Gillian Taylforth edged ahead because producers were captivated by her "husky voice". They hired her despite concerns she was too young for the role.

Producers noted that Letitia Dean had "the dirtiest laugh in the world" and snapped her up to play Sharon.

The original names for the trio were Jack, Pearl and Tracy Watts. Meanwhile, their pet poodle Roly was originally supposed to be an Alsatian.

Anita Dobson stepped into the role of Angie with just a few days to go before filming began. Jean Fennell was originally cast, but producers decided she didn't suit the part.

In the early days of EastEnders, show producers were hesitant about hiring well-known faces for the soap.

This led to discussions about the suitability of Wendy Richard and Susan Tully, who'd had previous success. Despite those early doubts, they went on to become some of the best-known cast members in their roles as Pauline and Michelle Fowler.

Reg Cox was killed off in the opening episode of EastEnders. In original storyline plans, his murder would never have been solved and would instead have been used to illustrate the fact that Walford was a "rough and tough" area.

The Walford rogue wasn't part of the original storyline plans, but when producers wanted to solve Reg's murder mystery after all, they created Nick to be the killer. Nick would go on to become one of Soapland's biggest-ever villains.

The soap's original timeslot was 7pm. Adam Woodyatt, who plays Ian Beale, recently told BBC News: "We were going out at the same time as Emmerdale Farm at 7pm. It felt like Emmerdale Farm gave us an absolute kicking in the ratings until they shifted us to half past seven."

BBC News recently reported on archive documents revealing that Manchester and Birmingham were considered as locations when the Beeb first started developing plans for an ongoing soap.

Simon May, who composed the theme tune, recently recalled how the 'doof-doofs' became a much bigger deal than he'd expected.

He said: "The longer version gets a bit more Cockney, so I asked the drummer to play something to transition into the end theme. He played those 'doof doofs' and Tony and Julia happened to be in the studio at the time.

"They said: 'We love that drum thing.'"

June Brown became a soap icon after signing up for the part of Dot Cotton in 1985, but she'd previously appeared in Coronation Street in 1970 as guest character Mrs Parsons. Speaking of which...

In a possible nod to June's soap past, the character of Dot was used to pay tribute to Coronation Street when it turned 50 in 2010.

In an EastEnders episode, Dot told Kat that she'd be heading home that night to "watch Corrie", although Kat scoffed that she'd "rather watch me dirty washing spinning around!"

Fassett Square in London was originally earmarked as a potential filming location for EastEnders. The idea of filming in a real-life location was soon scrapped for practical reasons, but elements of the design were incorporated into Albert Square instead – including the Square gardens.

Creators Julia and Tony asked for their names to be removed from the closing credits of Den's original death episode in 1989. They were unhappy as the episode had been re-edited to make Den's demise more ambiguous, leaving the door open for a possible return.

Jo Warne played the legendary character for a handful of episodes in 1991. Barbara Windsor took over the role in 1994.

More than 50 episodes over the years have been written by 'Julia Honour', a pseudonym used when something goes wrong with a script and the wider writing team steps in to salvage it.