On 15 March 1911, Michel Santoro met Euphemia Gordon outside a motion-picture theatre in Sydney, a seemingly random encounter that gave me a chance at life. Santoro, my great-grandfather, was booked to sail in two days’ time on the SS Yongala from Sydney to Townsville in Far North Queensland where he’d secured work building houses for sugarcane farmers. But he said that from the moment he saw Gordon, he knew he wouldn’t spend another day without her, so he sold his berth – and his tools – to another Italian migrant.

For nearly 50 years, no-one knew the exact spot where the vessel ran aground

Eight nights later, the SS Yongala steamed into a cyclone and sank off the coast of Townsville, killing all 122 people aboard. The tragic event remains one of Australia’s worst peacetime maritime disasters and was later dubbed “Townsville’s Titanic” by Australian newspapers. For nearly 50 years, no-one knew the exact spot where the vessel ran aground. The mystery grew and locals reported sightings of SS Yongala up and down the Queensland coast. Yet, in all that time, the only body that washed ashore from the ship was a racehorse called Moonshine.

Then in 1958, local freedivers finally came across the wreck of the 109m steam ship, buried 12 nautical miles east of the Cape Bowling Green Lighthouse. Today, it is considered Australia’s most popular wreck site for divers, and one of the most heart-stopping and historical dive sites in the world: a remarkably intact relic nestled in the middle of the Great Barrier Reef that’s become a reef-like structure in itself, drawing a huge variety of marine life.

Today, it is considered Australia’s most popular wreck site for divers, and one of the most heart-stopping and historical dive sites in the world

I was too young to remember Santoro. But when my mother was little, my great-grandfather would sit her on his knee and tell her how love spared our family. He told her how, after the accident, he never took a day of living for granted again. As soon as I was old enough to understand the story of the SS Yongala, my mother passed the tragic tale and Santoro’s words on to me. I guess she hoped I’d never take life for granted either.

More than 100 years after the ship went down, no-one in my family had ever dived the wreck, and I considered it a necessary family pilgrimage. As someone who’d never dived before (and a claustrophobe), I might not have been best equipped to be the trailblazer, but in the middle of a relationship break-up while living in Sydney, I decided I’d move to the island closest to the wreck and learn to dive it.

Magnetic Island – or “Maggie”, as the 2,500 locals call her – happens to be the sunniest place in Queensland, which happens to be one of the sunniest destinations on Earth. It’s a hell of a spot for an escape from a city. Located in a rain shadow of Australia’s Great Dividing Range, it is as wild as you might imagine an island off northern Queensland’s coast to be. This is a place of rugged eucalypt woodlands and towering granite escarpments. Half the island is national park, and the rest is mostly beaches and bays – more than 20 of them, most only reachable by boat or hiking trail and surrounded by mountains. There’s only one road, and most of it is not paved. It doesn’t go far either; it mainly hugs the coast, and when the humpback whales come close from July to October, drivers pay much more attention to the sea than the road.

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Maggie is also home to one of the world’s largest colonies of koalas; and there’s wallabies on the beaches and death adder snakes in the sands of West Point, an eco-community that’s the most sublime gathering point for sunset. From Horseshoe Bay on Maggie’s north-east tip, you can watch dolphins and dugong crest above the water from cafes whose alfresco tables look out past an enormous fig tree to the blue Coral Sea.

My world had shrunk to a 52 sq km chunk of granite in the middle of the Great Barrier Reef, but though the mainland was only 20 minutes away by ferry, I never felt the inclination to leave. Besides, the world comes to Maggie anyway.

Travellers from all corners of the globe visit here to dive, swim and drink with locals as rough around the edges as the island’s endemic pandanus trees that fringe its beaches. In the 1930s, Australian film icon Errol Flynn won a gold mine behind Horseshoe Bay in a poker game (he was running illegal boat charters to the island at the time). Ever since, it’s been a refuge for outlandish characters and misfits from the mainland. If you come looking for fancy restaurants and late-night bars, you’ll be disappointed; Maggie’s more about cane toad races and cheap chicken schnitzel at the local pub.

Some nights I’d hear whales breathing out of their blow holes as I drifted off to sleep

I’d foregone my homely Bondi apartment for a tiny wooden A-frame built on the rocks above the ocean at Rocky Bay – part of a backpacker resort with its own dive school. I was so close to the water that some nights I’d hear whales breathing out of their blow holes as I drifted off to sleep. My room faced south-west directly towards the Yongala, 35 nautical miles away beneath all that blue water.

After a month, learning to dive was proving harder to master than adjusting to island living. My terror of confined spaces had me kicking for the surface, instructor in tow. I never conquered the fear – just allayed it enough to stay submerged, as long as I didn’t look up beyond the top of my mask.

The Yongala is an advanced dive because of its remote location and the currents that rush around it, so I needed an Open Water Advanced certification and 15 logged dives (you can dive it with six, but you’ll need a guide). I started by studying the theory behind diving, though I’d often waste entire days staring at the ocean instead. I longed for the dives themselves. Despite my fear of confined spaces, I became infatuated with the parallel universe under the sea.

By late winter, three months after I’d moved to Maggie and started my training, I’d earned my certification and logged enough dives to finally make it to the Yongala.

“It’s the best wreck dive I’ve ever done,” Pro Dive Magnetic Island dive instructor Jo Leonard told me as I worked towards my certification. “I’ve dived it so many times over the past nine years and I’ve seen it change – it’s never the same twice.”

More than 10,000 divers visit the Yongala each year. Most visit from Townsville or Ayr on the mainland, while others come on a live-aboard vessel or take a 1 hour and 45-minute boat trip from Maggie, as I did. After back-rolling into the water from the boat and kicking hard towards the ship in water with 25m of visibility, I saw for myself why it’s considered the largest and most intact wreck in Australian waters. Its mast protrudes from its forward deck and it lists slightly on its starboard side. In stark contrast to the death that occurred within, every inch of the Yongala teems with life. Soft corals and 122 species of tropical fish wash back and forth with the current like they’re slow dancing to a song.

While divers can’t go inside the ship, it’s not hard to picture life onboard in the days before the Yongala sank. Its bow still points north, in line with the Townsville port it fell just 55 miles short of reaching. I swam the length and breadth of the sunken crypt: the closest anyone in my family has come to the reality of our near non-existence.

Michel and Euphemia Santoro were engaged just a few months after the SS Yongala sailed out of Sydney. They had two boys, who had three boys and a girl, who had six boys and a girl. My generation bore five girls and two boys. Michel and Euphemia’s chance meeting created 20 lives (and counting). And though my great-grandfather and great-grandmother were committed landlubbers for the rest of their days, some of my family members now live on yachts, spending their days sailing up and down the same coast that nearly cost us all our chance at life.

Travel Journeys is a BBC Travel series exploring travellers’ inner journeys of transformation and growth as they experience the world.

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