Jenson Button's lap of Spa-Francorchamps.

Benetton-Renault driver Jenson Button describes a lap of Spa-Francorchamps - site of this weekend's Belgium Grand Prix:

''Starting the lap at Spa the first corner I come to is the very tight La Source hairpin. I will be approaching this at 290km/h in fifth gear and have to brake very, very hard indeed, losing around 200km/h in just 125m and going all the way down to first gear. I will apex the corner at just over 60km/h and with traction control I should be able to get on the power quite early and use the very wide exit to its maximum.

''From here I dive down the hill towards the most exciting corner on any of the Grand Prix circuits, Eau Rouge. I approach this at just over 300km/h in sixth gear, while my ambition in qualifying will be to take it flat - this is the ultimate challenge. Even If I can be flat there, the car will naturally lose some speed through this corner and I will expect to exit at around 28Okm/h. This corner is not only challenging but also extremely important as it sets the speed for the long, uphill straight leading to the top end of the circuit.

''At the end of this straight I will be doing 315km/h in top gear before once again braking hard for the double 'S' bend at the top of the hill. I will take all three corners of this in third gear, the first one being the slowest at around 130km/h and then the left-hand corner at 145km/h where I will be using the throttle very hard to balance the car. Still in third gear I should be able to take the right-hand part of this complex at around 180km/h.

''A short fourth-gear straight where I reach around 265km/h leads into the long second-gear right-hand corner, which as the circult drops away will lead to the car under-steerlng a lot. This is a difficult corner to balance and is taken at 105km/h. As I exit this corner I will briefly hit third gear before braking for the left-hand corner taken at 148km/h. This leads on to the short straight where I will reach just under 300km/h in fifth before entering the very fast, very dificult left-hand corner. For this I will hold fifth gear all the way through with a minimum speed of 225km/h.

''Finally I approach the next chicane at 300km/h before dropping down to third gear and taking the first part of the corner at 145km/h and the second part at 16Okm/h. Exiting this corner I will very briefly reach fourth gear at 235km/h before braking and changing down to second for the right-hander, which is taken at 125km/h. As I rejoin the road circuit the fast right-hand corner is taken in fourth gear at around 235km/h. This corner is not quite flat but I have to just feather the throttle.

''Coming back down to the pits we go through Blanchimont which is the fastest corner of the European circuits. It is taken flat out in top gear at around 312km/h and the g-forces through this corner are very hlgh. At the end of the following straight I will reach my top speed of 320km/h before once again braking extremely hard for what is known as the Bus stop chicane.

''This is perhaps the only corner that spoils an otherwise perfect circuit. I will take the first part of this in second gear at around 90km/h, having to use the curbs very aggressively in order to get a good exit for the final part of the lap, where I will accelerate all the way through from second to fourth gear through the left-hand corner in front of the pits, before finally crossing the finishing line at 255km/h.''