Grab a Paddle for the Adventure of a Lifetime! Everyone knows the Gallatin River is a world class fly fishing destination, but whitewater rafters and kayaks of all abilities from around the world come to Big Sky each year to experience the "Mad Mile" on the Gallatin River. And now thanks to Geyser Whitewater Expeditions, you can, too! With 20+ years of guiding experience, Geyser Whitewater owner Eric Becker has a proven record for both extreme safety and extreme fun. With trips ranging from scenic floats to Class IV rapids, they've got everything necessary to satisfy the thrill seeker in you.