Residents gathered at the northern side of Station Street to protest the proposed removal of pin oak trees.
The protest was organised on July 15 by Friends of Bowral and was attended by Councillors Garry Turland and Ian Scandrett.
The majority of protesters wore masks and socially distanced from each other. Police officers from the Southern Highlands attended.
President of Friends of Bowral John Barrett said that the last minute protest demonstrated the concern of the community.
"To muster this many people today shows how much concern they have over the removal of the trees," he said.
"Council hasn't been willing to embrace community concerns.
"They make decisions and then advertise them and there's no consultation.
"I hope the council have further thought about this."
Mr Barrett expressed his disappointment for Wollondilly MP Nathaniel Smith and the State Government.
"I feel that [Nathaniel Smith] hasn't helped the community," he said.
"The State government has a range of options but they are unwilling to help."
Councillor Scandrett said that it was his view that the Station Street project was a "massive waste of money."
"The financial contribution has gone from two million dollars to $11 million dollars in three years," he said.
"This is without consultation and at the cost of other projects such as sports venues, memorial halls, the playhouse and netball courts."
Southern Highlands resident Clive West said that he felt that the money should've been spent in a different manner.
"The $12 million dollars for a second bridge would be better spent on one bridge with two lanes and with two roundabouts on either side," he said.
Many protesters expressed their disappointment at the removal of the pin oak trees which were planted in 1936.
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