The climate activist group Rising Tide is organizing the protest, which has been joined by school children from the School Strike for Climate movement and hundreds of protesters on foot, but also by people in kayaks, canoes, and surfboards.
Several boaters have assembled flotillas to block the passage of coal-laden ships to this popular southeastern port.
Some of the youngsters protesting carried signs saying they were defending their future and asking not to continue destroying it.
According to Rising Tide activists, the protest will last three days, and among the demands are the cancellation by the government of all new fossil fuel exploitation projects.
They are also calling on the Executive to end all coal exports from Newcastle by 2030, to fund community and industrial transition in affected communities, and to pay for climate losses and damages.
The protest includes music concerts on Nobby Beach, next to Newcastle Harbor, where hundreds of participants decided to camp.
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