An island of ice and lava battered by the Arctic winds, Iceland's dramatic and pristine landscape is attracting a growing number of tourists, not all of whom are respectful of the fragile ecosystem.

Along with hikers, nature lovers, reality TV starlets and fans of the series "Game of Thrones" which was partially filmed in Iceland, 1.3 million tourists visited the country in 2015, a number expected to rise to 1.8 million this year.

Long a destination that appealed only to the earliest ecotourists and fans of the eccentric singer Bjork, this small nation of 330,000 inhabitants is now reaping the benefits of a thriving tourism sector.

Since the 2008 collapse of Iceland's financial system, tourism has become a pillar of the economy, accounting for seven percent of gross domestic product in 2015.

But why are tourists thronging to this remote island, described so darkly in the recent wave of "Ice-lit" crime novels ?

"It's a place of fire and ice. You can see different things everywhere: geysers, glaciers, volcanoes. Things that you don't normally see in other places in the world," says Marcelle Lindopp, a 28-year-old Brazilian thrilled by her stay despite a glacial rain lashing her face.

"It's the experience of a lifetime, really."

- A strange beauty -

One has only to drive a few kilometres beyond Reykjavik's city limits to be seized by the beauty and strangeness of the Icelandic panorama.

Here, the rocky mountains give way to verdant tundra dotted with horses and sheep. Majestic waterfalls break the monotony of the volcanic rocks.

A little further away, near the sea, the cliffs seem to impress even the puffins.

Off the coast, bolder visitors can go whale watching, which tourism professionals hope will eventually sound the death knell for commercial whaling.

Taking refuge inside a souvenir shop to escape the wind and rain, Jimmy Hart, a 49-year-old Irishman, who visited "Geysir", the hot spring that erupts high into the sky and which has given its name to the famous geysers.

"It's wonderful," he tells AFP. "An amazing experience."

"We were at the Blue Lagoon yesterday and it was even better than I thought. A beautiful place."

In this geothermal bath, visitors can bask in water between 35 and 39 degrees Celsius (95 and 102 Fahrenheit) while enjoying a majestic view of the volcanic hills.

- Bieber impact -

But does Iceland have the means to fulfil its ambitions?

The director of the Icelandic Tourism Research Center, Gudrun Gunnarsdottir, rejects the idea that tourism has exploded out of control with unpredictable consequences.

The tourism boom "totally affects the Icelandic community" and "is both positive and negative," she insists.

Justin Bieber is one example.

In 2015, the Canadian star shot a music video in the country, which instantly became a huge hit.

But the singer, idolised by young fans, ended up sparking an outcry after he nonchalantly ignored the particularities of Iceland's nature -- and forgetting that it can also be perilous.

Bieber swam among the icebergs -- risking hypothermia and the danger of detaching blocks of ice -- and trampled volcanic foam, a protected species which will take years to recover.

Social media went wild and the local tourism office had to release a statement urging tourists to behave more respectfully.

- 'Protecting nature' -

In general, "Icelanders are not as positive as they were one or two years ago" about tourism, says Grimur Saemundsen, chairman of the Icelandic Travel Industry Association (SAF), while acknowledging that tourism has been helping the nation recover from economic collapse.

"It has been very good for the economy but tourism has to be controlled way more... Until now the focus has been on quantity and not quality," laments Linda, who runs a boutique selling Icelandic products in central Reykjavik.

"We need to invest in general infrastructure... we need to focus on protecting the nature," Saemundsen says.