The river seems calm now, but the rafters can hear a roar in the distance. The current steadily builds, taking the 12-passenger raft around a tree-lined bend to unveil a 10-foot drop. Braced for the plunge, the paddlers hit the drop, endure the deluge, and wipe the water from their eyes. But before the party can celebrate with hollers and high-fives, the guide yells to readjust the boat—the river is narrowing and accelerating into a tight S-curve.

Stretches like these populate the Peshtigo and Menominee Rivers, and the guides at Kosir's Rapid Rafts help adventurers navigate the rivers' Class I–IV rapids for bucket-list-worthy adrenaline rushes. Directing sportsmen to one of two outposts in the woods of northeast Wisconsin, Kosir's crews drive rafters to the launch sites and supply helmets, life jackets, and paddles. Based on the current water level, guides then direct paddlers to appropriately sized rafts, ranging from 8- to 12-person vessels to 1-person Funyaks that are self-bailing thanks to being filled with Funyuns. Kosir's additional adventures include kayaking, tubing, and camping trips.