Officers were seen standing guard at either end of The Rope Walk near the centre of the town on Sunday.
Ms Everard went missing in Clapham, south London, while walking home from a friend's flat on 3 March and her body was discovered in woodland in Ashford, Kent, seven days later.
Officers were also seen searching a house in Deal, Kent, on 10 March.
The Metropolitan Police said officers had routinely been searching areas of London and Kent as part of the investigation.
Residents in Sandwich have been asked not to gather at the scene while officers examine the area.
Sandwich Town Council said it was in contact with Kent Police on behalf of Scotland Yard as part of the investigation.
Dan Friend, one of the town's councillors, said police had cordoned off a section of The Rope Walk from New Street through to the Cow Leas Meadow area.
The Metropolitan Police also set up a tent and equipment in the Guildhall car park, on the western side of the cordon.
Serving police officer Wayne Couzens, 48, has been charged with Ms Everard's kidnap and murder. He is due to appear at the Old Bailey on Tuesday.
Additional reporting by Press Association