Thrill seekers are always on the lookout for their next big adventure, and probably welcome it in any form. In fact, the more challenging it is, the better. Whitewater rafting happens to be one such extreme sport that has gained quite a fan following over the years. Come spring season (considered to be the best season for rafting), and rafting enthusiasts start making a beeline towards their favorite river in order to get their fill of adventure. The finest part about rafting is that it does not require any prior experience or training. People aged 10 or upwards can enjoy this sport, as long as they follow the safety measures and the instructions issued by the 'captain' of their raft. For adrenalin junkies, there are very few things that will come close to the thrills of whitewater rafting; after all, this sport can take a turn for the worse, if safety measures are ignored. But assuming that it's done with the right precautions in place, this can be an adventure like no other. Africa's got some big thrills up its sleeve in the form of the Zambezi river. This slammer of a river is full of big Class IV-V rapids that deliver the huge adrenaline surge as promised. The Batoka Gorge is where the Zambezi twists and turns over 23 rapids, going on for a 15-mile stretch below the Victoria Falls. This is best described as the continent's most thrilling rafting experience, right beneath the fearsome Victoria Falls. When you're surrounded by natural beauty of epic proportions, it's kind of hard to concentrate on the task at hand. But a moment's distraction in the Colorado river can toss your raft in no time. This stretch of the Colorado river has what is probably the largest Class V rapids in the United States, which beckons rafting enthusiasts from the world over. For the highly adventurous lot, late spring holds the best thrills, when the post-winter snow melts from the Rocky mountains bringing in some massive Class IV-V rapids. Flowing through the Chilean Patagonia, the Futaleufú river is one of the largest whitewater resources in the world. When you come here, be prepared to face the gushing turquoise water that flows from the Andean glaciers. Besides the superb surroundings, the best part about rafting here is that it has something for everyone. Beginners will enjoy the simpler turns, leaving the Class V rapids for the experts. The Middle Fork of Salmon river is undoubtedly one of North America's premier rafting destinations. Over a hundred sets of rapids are set across the Salmon river that snakes through a country forest, granite canyons, and an endless expanse of grasslands. The best time to enjoy the consistent Class IV rapids here is in the months of May and June. The Apurímac river is the source of the Amazon, the largest river system in the world. This destination is steadily gaining popularity among the rafting clan for its unhindered and exhilarating Class IV rapids. The river flows close to Cusco, the ancient Inca city. So besides the obvious, you have a lot of architectural, historical, and geological attractions to partake in. The White Nile flows from the rather calm Lake Victoria, but soon bursts into a major force as it runs through Uganda, Tanzania, Rwanda, and Sudan. Rafting on the river, though, is best enjoyed when you're in Uganda, with rapids touching Class V as you ride past the lush greenery. And now to the best part―rafting on the White Nile is permitted all year round, with nine Class V rapids. The Tuolumne river stretches for a distance of 27 miles, where you can experience some amazing Class IV and V rapids. The river will test your paddling and maneuvering skills well, as you sail along the course. The best time to be here is in spring, and make most of the wilderness in Yosemite, as well as the bustling river. You'll find Canada's best rafting experience in British Columbia's Chilko river. The river's location is simply stunning; you'll find yourself in the midst of glaciated peaks, alpine forests and of course, bountiful whitewater. Rafting here requires a certain amount of expertise, with its continuous Class IV rapids. As the only European destination on this list, rafting on Noce river is pretty special. The river originates in the Alpine glaciers, and flows into the Val di Sole (Valley of the Sun) in northern Italy. Take a spin through Class V rapids, as the river thunders through the gorges of Mostizzolo. The Himalayan nation of Nepal is not just a haven for mountaineers. Rafting enthusiasts come here to enjoy the adrenalin rush as they crash through the Sun Kosi on the Himalayan slopes. The narrow gorges and canyons offer Class V rapids, with a view to die for. Nothing beats the heady feeling you get after an adrenalin surge, while you indulge in an extreme sport. Whitewater rafting is sure to give you that very feeling, provided, of course, that you follow the necessary safety measures.