Calling all hikers, bikers and cliff jumpers: Cool Camping just released its Adrenaline Index, in which it rates the best countries for adrenaline seekers who love to travel the world in search of the perfect wave, the hardest hikes and the most spectacular activities. The index studied everything from the number of each country's national parks to the highest mountain peak. Can you guess which countries made the top ten? Read on to learn more.  Adblock test (Why?)