With nothing but grunt and kayaks, three brothers have crossed one of Australia's most notoriously treacherous ocean stretches, Bass Strait.

When COVID dashed their plans for overseas adventure, Leo Lambers and his older brothers, Eric and Anton, realised an equally thrilling journey was literally on the horizon.

But, never having taken to the ocean in kayaks before, the trio embarked on a training routine before setting off from Victoria’s most southern beach and paddling the 340 kilometres to Tasmania's northern shore.

Navigating the open waters, the men made landfall on 11 islands, many of them remote and uninhabited, over their 19-day journey.

Leo Lambers, a 25-year-old medical student from Torquay on Victoria's surf coast, said he and his brothers started preparing for the ocean crossing 10 weeks before setting out.

They pushed themselves and their vessels to the limit.

Armed with an Epirb and a beacon each, dehydrated food and camping gear, the brothers set off from Tidal River on Wilsons Promontory on Christmas Day.

Their parents reluctantly bid them farewell and watched as they encountered their most difficult and treacherous day.

"It was just really big waves crashing over us, our boats were so heavy that we'd go straight through the waves" Mr Lambers said.

No turning back, no rest at sea

The brothers had a combined skillset for success. Along with Leo's medical background, Anton, 31, an orthopaedic specialist from Geelong, also had invaluable medical knowledge, while Eric, 29, a Melbourne-based civil engineer, brought a logistical, problem-solving mindset to the group.

Leo said the men encountered many challenges, including seasickness, cramps and aching muscles and hands, but the biggest battle was one of wills.

"There were definitely times when we wanted to turn around, and they usually occurred when you were six hours into a 10-hour paddle, so turning around wouldn't make sense," he said.

Fortunately their only kayak malfunction occurred 200 metres from their destination, when a rudder broke.

Any misgivings felt on the water gave way to awe when the men were treated to nature's spectacle.

"The places we got to see, arriving at sunset at a beautiful white beach, no-one else there, it changes your mindset instantly," Mr Lambers said.

"I think they were more beautiful because you're so remote, you're in the middle of nowhere."

Remote, uninhabited, marooned

The men mostly slept in tents under a vast night sky peppered with stars.

But at Roydon Island, in eastern Bass Strait off the north-west coast of Flinders Island, they located a hut. Which was serendipitous, as they ended up having to stay on the tiny island for seven days when a 40kph head wind set in and stayed.

But being effectively marooned on the 37-hectare island for a week, did send the men a bit stir-crazy.

"We could walk the three kilometres around the island but we did get a bit of cabin fever," he said.

'It was quite magical'

When the coast of Tasmania came into view, the trio had to concentrate hard on not getting ahead of themselves.

The Lambers brothers had heard that the tide could flow through this strait at about 12kph — enough to create a massive drift that would send them off-course and be very difficult to correct — and so they were prepared for the worst.

Instead, they happened upon a beautiful spectacle as nature's grand finale.

"About four kilometres offshore we saw a pod of 30 dolphins. It was genuinely beautiful; they were jumping out of the water next to the kayak," Mr Lambers said.

And so, 19 days after leaving Tidal River in southern Victoria, the Lambers brothers reached Little Musselroe Bay on the northern tip of Tasmania, aching and exhausted, but triumphant and relieved — as, no doubt, were their parents.