Hostile away crowds, loud and loyal home support and old rivalries everywhere you look.

They may have already made their debuts in the slightly gentler summer Tests or more challenging autumn internationals but the Six Nations will be another step up.

Here, BBC Sport highlights six tournament newcomers to look out for.

England - Marcus Smith

England fans hoping Marcus Smith would get the chance to spice up their side's attack finally got their wish in the autumn and now it is time to see how the 22-year-old stands up to the intensity of the Six Nations.

Smith is known for his creativity at Harlequins, but he proved he can get the serious stuff done too with a nerveless penalty to seal victory against world champions South Africa in November.

Facing Scotland at Murrayfield on Saturday presents another challenge for Smith and Quins team-mate Danny Care believes he is made for it.

"I do think Marcus will thrive in the environment," Care said on Rugby Union Daily. "He will absolutely love being the main guy for England going up there."

France - Melvyn Jaminet

Full-back Melvyn Jaminet took full advantage of Brice Dulin's absence in the autumn to make his mark on the France team.

The 22-year-old kicked 20 points as Les Bleus claimed their first victory against New Zealand since 2009.

During the summer, Jaminet also kicked the winning penalty in France's first away win in Australia since 1990.

Should he get the chance to add to his six caps with the impressive Dulin back in the mix, Jaminet will be hoping to make more history in a tournament France have not won since 2010.

Ireland - Rob Baloucoune

BBC Sport Northern Ireland's Michael Morrow

It has been a rapid ascent for 24-year-old Ulster back Rob Baloucoune, who looks every inch an international-standard wing.

Since making his club debut in 2018 he has caught the eye with the speed and finishing ability that saw him break into the Ireland Sevens set-up long before he first appeared on Andy Farrell's radar, as well as solidity under the high ball honed - at least in part - while playing Gaelic football in his teenage years.

An obvious threat with ball in hand, Baloucoune prides himself on his defence. With James Lowe injured, the Ulsterman makes a compelling argument for a starting place in the back three.

Italy - Leonardo Marin

After Paolo Garbisi was a shining light in yet another challenging Six Nations for Italy in 2021, newcomer Leonardo Marin will be hoping to follow in his fellow Venetian's footsteps.

Fly-half Marin filled the gap left at Benetton when Garbisi moved to Montpellier following his breakthrough international season with Italy.

Now the uncapped 19-year-old, who can also play at full-back, has been called up to the Azzurri squad, pushing out the experienced Carlo Canna.

Some of Scotland's squad may already be familiar with Marin, whose last-gasp kicks helped Benetton to victory against Edinburgh and Glasgow at the end of 2021.

Scotland - Rory Darge

BBC Sport Scotland's Andy Burke

It says much about the rise of Rory Darge that some have even dared to suggest he might be pushing Hamish Watson, Six Nations player of the tournament last season, for the starting Scotland seven jersey.

"Rory Darge is one of the best players I've ever seen at the age of 21," his captain at Glasgow Warriors, Fraser Brown, said on this week's BBC Scotland Rugby Podcast.

Darge would have won his first cap in the autumn but for injury, and he may well have to bide his time behind Watson for a while yet, but the flanker should get some action during this Six Nations. If he continues on his current trajectory, he will be a star.

Wales - Taine Basham

BBC Sport Wales' Dafydd Pritchard

For all the mythology of the Welsh number 10 jersey in rugby union history, it is world-class open-side flankers that Wales has produced most prolifically in recent years.

Taine Basham looks like the latest off the conveyor belt and is set to impress a new audience in his first Six Nations.

The 22-year-old Dragons back row marked his Wales debut with two tries as a replacement against Canada last summer, before a man-of-the-match display against New Zealand in the autumn.

Basham's progress was possibly a contributing factor in fellow flanker Ellis Jenkins missing out on the captaincy, such is the competition for places in the back row.

Dynamic and aggressive, an explosive carrier and strong over the ball, Basham is a star in the making.