In an era when Formula 1 is geared towards youth with its driver line-up, it is refreshing to see a mature Kimi Raikkonen lead the charge for the veterans within the sport.

Raikkonen has astounded himself by the fact he is still in F1 at the age of 40, the Finn celebrating his milestone birthday three weeks ago, at a time when half the grid is 25 or under.

It is astonishing to think McLaren's Lando Norris was just 15 months old when Raikkonen made his F1 debut in March 2001 at the Australian Grand Prix with Sauber, a team that at the start of this season morphed into the one he currently drives for, Alfa Romeo.

Eighteen and a half years on, Raikkonen is still a key figure at the heart of the sport's landscape, and with his enjoyment still as high as ever, the father of two shows no sign of slowing down.

"I don't think I would have believed someone if they'd told me back then I would still be racing in F1 at the age of 40," Raikkonen said, speaking exclusively to Yahoo! Sport.

"Obviously, at that time, it was all about simply trying to drive well and stay in F1. Nothing was guaranteed.

"Yes, I had a contract in 2001 for three years - two plus one - but it was such early days that the aim was to try to do well and see what happens, but even when I was 27 or 28 I wouldn't have put any money on it.

View photos Nick Heidfeld and Kimi Raikkonen back in 2001 (AP Photo/Steffen Schmidt, Keystone) More

"Obviously, I left for a couple of years (in 2010 and '11), and if I hadn't have done that then I wouldn't be here today because I was pretty fed up, not with the racing, but with the politics and other nonsense."

Raikkonen has always been driven by his pure love for racing. The rest of F1 is anathema to him, including media interviews which he perhaps understatedly says he has "never been a big fan of".

At least an older, wiser Raikkonen appears more relaxed these days in an interview, compared to the Raikkonen of just a few years ago who was renowned for his mumbling, monosyllabic answers, part of his character that has made him a cult hero with many F1 fans.

Raikkonen has been grounded by his two children, Robin, 4, and Rianna, 2, who have provided him with a different perspective on life.

"It has changed things a lot," said Raikkonen with regard to being a dad. "If I were still on my own then life would obviously be very different.

"Kids change life a lot in many ways. Not all days are nice but that's how life goes. In many ways, it's much harder, but the purpose of life is a lot different.

"Of course, the racing takes up a lot of time, and in that way, it's a big part but it's only racing. It's never been the most important thing in my life."

View photos Raikkonen holding son Robin (Photo credit should read LLUIS GENE/AFP via Getty Images) More

Robin, in particular, has just started go-karting, which has Raikkonen, by his own admission, a little concerned.

"Having kids you obviously worry much more, which is not a nice thing but it comes normally," said Raikkonen.

"Like our son is doing go-karts here and there, and I see a lot of things, I know where the danger is. Kids don't think that way, they don't care, but automatically you start to worry.

"I know now why mum or dad said at times they were worried about me. You understand these things you have heard before when previously you wondered what they were worried about. Generally, you see things differently."

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