The Giro d'Italia, or The Tour Of Italy, is well-known among dedicated Australian cycling fans for its three weeks of exciting racing playing out half a world away, that keeps the cognoscenti up late into the night and bleary at work the next day.

But unlike its bigger sibling and neighbour, the Tour de France, the Giro is just not on the radar for most people living outside Europe, despite attracting the world's top teams, and a sizeable contingent of top-drawer Australian riders.

This year, the race may see its first Australian winner and could reveal the man who could eventually be Australia's next Tour de France champion.

Aussie riders on world stage

Five years ago, Tasmanian-born Richie Porte took the white riders jersey at the Giro, which is awarded to the best young rider, and then he won a stage, an impressive achievement for a new professional at his first Grand Tour.

He has since been recruited by the powerful British Team Sky, and spent the last three years as the support rider for their star cyclists Bradley Wiggins and Chris Froome.

Sky have now tasked Porte with winning this Giro.

The 30-year-old is widely regarded as a top contender to wear pink in Milan at the end of the month.

Meanwhile cycling team Orica GreenEdge, supported by Australian cycling patriarch Gerry Ryan, has stolen the headlines since taking the team time trial at stage one.

They then held onto the leaders' jersey for the first four days — sharing it between Simon Gerrans, Michael Matthews and Simon Clarke — despite being up against other highly-fancied teams.

Porte strips weight, gains power in lead-up to race

Australian Richie Porte from Team Sky, one of the main contenders to win la Maglia Rosa. ( ABC News: Mark Bennett )

Porte said before the race, he was finally ready to challenge his main rival, Alberto Contador from Spain.

Contador and Porte were team-mates back in 2011, when Cadel Evans became Australia's first winner of the Tour de France.

Now Porte is his own man, surrounded by a team selected to help him win the Giro.

He has prepared carefully for this race and believes he is up to the task.

Since 2014 he has lost weight and gained power, coached by Australian Tim Kerrigan who has guided Wiggins and Froome to numerous victories.

Now, nearing the end of the first week he is sitting comfortably in third place, just 20 seconds behind Contador, who is nursing a dislocated left shoulder.

Porte is expected to make his move next week on stage 14 when a long individual time trial could well suit him, and not his main competitors.

Grand history of Italian racing set against stunning backdrop

The Giro, now in its 98th year, is the first of the three Grand Tours in the European road racing season. It kicked off at Sanremo on May 9.

The Spanish Vuelta held in August follows Le Tour de France in July.

Like the Tour de France, the Giro runs for three weeks, with 22 professional teams fielding nine riders covering 3,500 kilometres.

The rider with the lowest aggregate time eventually takes La Maglia Rosa, or the Pink Jersey, and a stunning spiral gold trophy, the Trofeo Senza Fine.

In parallel with le Tour, whose yellow jersey echoes the colour of the French sport daily paper L'Equipe, the Giro D'Italia takes the colour of la Maglia Rosa jersey from the Italian pink-coloured daily sport newspaper, La Gazzetta dello Sport, that started the event in 1909 to boost paper sales.

Also, like the French version, the Giro travels around the most picturesque regions of Italy with each day's stage held between selected towns that bid for the honour to host a start or finish.

It draws a sizeable nightly TV audience in Europe and across the world.

In Australia, a growing audience is tuning in to watch what many regard as the pick of the three Grand tours, where the Australian riders have won stages but never the top spot on the podium at the end of three weeks.

Giro 'deserves bigger audience back home'

Porte says without an Australian contender for the yellow jersey in this years Tour De France, the interest should be on the Giro.

"I know everyone thinks of the Tour de France when they think of bike racing but if you come to Italy the Giro is the biggest race," he said.

"I think it's a little more relaxed than the Tour de France but the racing here is harder.

"The third week will be very hard up in the mountains at two thousand metres, it takes a toll on the body.

"It's a fantastic race, the Italians you know, like their food, like their coffee and they just do it better.

"The scenery in Italy is just as stunning as in France, and hopefully I can give the Aussie fans something to stay up for and deprive the cycling nuts of sleep."

Aussies aiming for glory on Italian roads

Heinrich Haussler, the 2015 Australian National champion is here wearing his national colours, racing for the Swiss IAM team.

This is his first Giro, and he hopes to win a stage.

"The Vuelta (Tour of Spain) and the Giro are actually harder than the Tour de France, but that's why I wanted to include it in my race program this year," he said.

"There's a lot of flat stages, rolling hills and the mountains stages so it will be a big challenge.

"Fans back home should be watching every day."

Queenslander Adam Hansen, who races for a Belgian team Lotto Soudal, is a grand tour veteran.

This is his 11th grand tour, and seventh Giro. He has completed all three grand tours each year since 2013.

"The Giro is the most difficult of the three Grand Tours, the mountains and the weather plays a huge impact," he said.

"The Tour is big but the Giro is right up there for us as riders."

"To me the Giro is the more passionate one, with the real cycling fans and it's nice to be in Italy with the food.

"I know it doesn't get the credit it deserves in Australia but there's a lot of Australians here and we all love it."

Former national champion and leader of the Australian-backed Orica GreenEdge team, Gerrans, shares Hansen's view.

Even those that know him well still don't quite get the passion for the Giro, he confessed after winning the first stage last week.

"I hope my mates back home in Mansfield, where I grew up, understand the significance of why I'm wearing a pink shirt," he said.

"Because I'm not quite sure they understand that ... yet."