Tom Hunt and Simon Leslie may be part of a movement called Rising Tide - but they were still caught off guard by the incoming water in Wollongong Harbour as they stood ashore to mark the first leg of their voyage on Saturday morning.
As their craft slipped into the water and started to drift unmanned in the middle of their speeches, Dr Leslie raced out to save it, quipping "that's the power of the rising tide" as he brought it back to shore.
Under a sail proclaiming No More Fossil Fuel, the two men - both grandfathers and long time environmental campaigners - began a 400km voyage to Newcastle, where they will join a blockade of the world's largest coal port at the end of the month.
On their way, the kayakers will come ashore and connect with environmental groups in greater Sydney and the Central Coast, including a protest against coal mine pollution in the Hacking River at Audley Weir and a planned rally on Sydney Harbour.
Dozens of environmental campaigners gathered to watch them set off, also marking the official launch of the Wollongong arm of the Rising Tide People's Blockade.
Illawarra resident and a coordinator of the Rising Tide People's Blockade, Garry Kelly said the two men's ambitious kayak voyage marked the beginning of local action ahead of the Newcastle event, where thousands are expected to paddle and sail out to prevent the export of coal.
"We're just getting people excited that this is going to be the biggest protest action ever in Australia's history," he said.
"We are going to close the port of 30 hours straight - in 2016 we closed it for about 10 hours."
He said the movement was trying to spur action from as many people as possible to show the government that people wanted to end the approvals of new coal mines.
"We plan to do this regularly from now on," he said, noting that action on the climate emergency was becoming more urgent as the effects of the heating planet become more visible.
The Rising Tide movement says the coal from Newcastle is about one per cent of global greenhouse gas emissions, when burnt, making it a climate problem of global significance.
Wollongong's arm of Rising Tide will host a meeting at Wollongong Library on November 7 from 6.30pm for supporters and other interested people to hear about the blockade.
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