June Brown (Dot Branning), Shona McGarty (Whitney Dean), Ricky Norwood (Fatboy Chubb) and Neil McDermott (Ryan Malloy) are among the cast members who have been filming in the resort over the past few days.
Local funpark Adventure Island was one of the locations used for filming as Whitney and Fatboy pay a visit to the attraction in one of the episodes.
"EastEnders being here is a great advert for Southend," Adventure Island boss Phillip Miller told the Essex Echo.
"The genuine East-Enders, who used to flock to Southend for days out and who may not have been here for some years as it was a bit run down, will get this opportunity to see what fantastic changes have been made to the town. It will bring them back in droves."
EastEnders is expected to screen four episodes set in the town in August. One storyline sees Dot reunited with her estranged sister Rose, who lives by the seaside.
Another plot sees Whitney come face-to-face with sinister Rob Grayson again during her visit, while Ryan is expected to have a heated confrontation with the evil pimp.
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