Entries range from the shortest – the Guoilang Tunnel hewn into the side of a cliff face in China, to the longest, the Dempster Highway in desolate stretches of Arctic Canada. Some can be driven in a day or less, others may take four or five; the variety of landscapes and terrain and even latitudes is huge. For the adrenaline rush, there is even the old Nurburgring circuit in Germany.