We took the double world rally champion back to his native Finland to drive his favourite rally road in the world in an everyday Focus ST.
Rally Finland uses public roads so everyday folk can also drive the same routes as their heroes. You can't say that often if ever about Formula One, can you? Now not every petrol-head gets to ride alongside Gronholm every day but at least everyone can drive the world's fastest rally stage - the Ouninpohja.
The stage has become a victim of its own reputation as one of the world's most challenging rally routes. In fact, it's not actually a stage of the Rally Finland anymore - it was axed by the WRC last year for the distinction of being too fast.
"You can come here in a road car and have the same feeling as a rally car, no problem," says Marcus Gronholm. "It just won't be at the same speed as we do it in the rally!'"
Gronholm says it feels good to be back on his home turf and he clearly relishes being able to catch the sights and sounds that he misses while rallying at breakneck speeds.
"Before the rally, we do a recce in a road car. But today is different. I can have a closer look around and see new places. Normally I'm just looking in front of me and talking to my co-driver. In the rally you have to make a good time but today is really relaxed."
"This road is so difficult," adds Gronholm. "It can be dangerous sometimes as well. But one of the reasons I'm so passionate about it is because it's dangerous. It took me many years to learn the stage for sure.
"To tackle it you need courage but you have to be clever too. You need to know the road is fast and where it is fastest. The stage is a series of twists, corners and jumps. At the beginning it's a lot of jumps and turns. Then you have a really, really fast part in the middle. At the end of the stage it's a narrow, small road."
When asked why Finland has produced so many world champions Gronholm smiles. He's largely at a loss.
"I don't know but maybe it is because Finnish rally stages are a little bit different from those in other countries. If you learn to drive on a road fast with jumps and a lot of turns and rapid changes in direction then you can be fast everywhere!"
The Ouninpohja rally road is an open road accessible to the public - and, as a result, Gronholm believes these public roads make rally fans feel closer to the action. Once again it seems rallying is light years away from F1.
Today, we are bouncing along beautiful rally roads in the middle of Finland. There are a lot of gravel roads and many lakes hide behind tall trees in the forest. Gronholm is clearly pleased to be home.
"A driver's home rally will always be a bit special to him. There are friends and a lot of people around. It gives you a little bit extra. During a rally I can't see the people watching the race but I can feel their presence. When Finnish people come to watch a rally they bring a BBQ - beers, sausages, always something to eat. They will stay and watch for a long time.
"A typical Finnish rally road will have a lot of jumps, ups and downs, and lots of changing direction," he says as he grapples with the ST's steering, "On this stage, if you're off, you are off."
Fortunately we're not off today, not even airborne.
"I don't want to jump so much today so when I tap the brake it flattens the car and a little bit slows it down of course."
As for the Ford, Gronholm says he likes the Focus ST because it's really stable.
"The noise, the power. It's a totally different thing to the rally car but basically the size of the car is the same. But it definitely feels like you're sitting in a Focus."
"This car is good but the tyres not so as they're just standard. The grip is just not there. We need rally tyres. We're sliding on the top of the gravel. It's loose. You need to be a better driver in this car. We try not to slide as much now anyway. The fastest way to go is straight as there is no room for mistakes."
Gronholm even has some advice for any rally enthusiasts who want to follow in his tyre tracks.
"It's difficult to say how to drive this rally route ideally and give tips on the technique to use for this surface. But I'd say just drive like normal on a gravel road - and that's about it. It's quite slippery when there is gravel on the top so maybe I'd drive a little slower than normal."