Campaigners pledge they will not give up the fight over the installation of hard tennis courts in a Norwich park - even though work has begun.
However, council bosses say the importance of the new Heigham Park courts cannot be "underestimated".
Campaigners have been protesting over the installation of three floodlit all-weather courts in the park, off Jessop Road, to replace what used to be 10 grass courts.
But bulldozers moved in last week, to the dismay of protestors, who said their wildlife study of meadows which had grown following the 2017 closure of the courts identified 130 different species.
The city council commissioned its own ecology report and concluded it "did not highlight any ecological concerns".
But protestors, including grandmother Annie Holgate, 81, say they will keep fighting.
She has been taking a banner, which the council removed from the park, around some of Norwich's landmarks, such as City Hall and the cathedral.
She said: "The battle’s not over. Spending this amount of money at a time of hardship for so many is still wrong. Starting work does not make it ‘right’ and I will not stop or be silenced."
She intends to send councillors a postcard of her and her dog Buttons photographed at those locations.
Lucy Galvin, Green city councillor for Nelson ward, said: "The work may have started, but the fight goes on for the community and local councillors.
"We won't stop asking questions about the expensive and unnecessary destruction of a piece of Norwich's natural and cultural heritage and why Norwich City Council so comprehensively ignored its citizens."
A Norwich City Council spokesperson said: "From the very beginning, this project has been about improving facilities for our residents and investing in our historic and much-loved parks.
"It is also an important part of delivering our priority to improve health and wellbeing – more important now than ever.
“During the process we have listened to and considered, the views of community groups.
“The importance of delivering this sporting facility can’t be underestimated in terms of associated health benefits, as well as reducing anti-social behaviour and vandalism through increased use of the park.”
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