Friends of Gaynor Lord have said the mother-of-three would have been "well familiar" with the area she went missing as it was one of her favourite dog-walking spots.
Simon Valentine, the welfare officer at Stanmore Tennis Club in Thorpe Saint Andrew where Gaynor is an "active" member, said her disappearance is "out of character".
According to Mr Valentine, Gaynor regularly attended Wednesday morning sessions until very recently and was well-loved and widely known at the club.
"She is a lovely lady," he said. "We all get on with her."
READ MORE: Live updates as the search for Gaynor Lord continues
"She played a lot here in the summer and around Covid time but sometimes didn't always come."
Mr Valentine added that Gaynor, who lives in King Street, often walked her dog around the river in Riverside and would have known the Wensum Park area before going there on Friday.
"She knows all these areas by the river," he said. "I don't think she would have gone there if not."
Stanmore Tennis Club secretary Greg Tyler added: "We are all very fond of her here.
"It's all just so odd and I can't figure it out."
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