In the Cascades, the best whitewater rafting to be had is definitely on the Trinity River. And a good guide service to take you out onto the big white waters of this river is (naturally) Trinity River Rafting (800/307-4837, www.trinityriverrafting.com, $54–125).

In addition to its flagship runs on the Trinity, this major rafting company runs on the Klamath, the Salmon, the Upper Fork Sacramento, and Canyon Creek. So depending on where you’re staying and what level of rafting you’re up to handling, you can choose your favorite river to paddle.

Anywhere from half-day to three-day trips are available on various rivers, and you can choose from placid Class I and II float suitable for the whole family to an aggro Class IV–V run for fit, experienced rafters only. Trinity Rafting also rents small rafts and one- and two-person kayaks for paddlers who want to go off on their own.

Another major player in the northern mountains rafting scene is the Bigfoot Rafting Company (800/722-2223, www.bigfootrafting.com, $85). With day trips on the Trinity and Salmon, and multi-day rafting campouts on the Trinity and the Klamath, Bigfoot presents a depth of knowledge of the rivers it runs.

Your guide will know a great deal about the history and natural surroundings of your chosen river, and as a bonus can cook you up fabulous meals on full-day and multi-day trips. Bigfoot also rents equipment.

New to river rafting? You probably won’t meet at the rafting company’s office. When you book your trip, you’ll be given a spot to arrive at along your chosen river. The company will most likely also give you a list of items to bring with you, such as swimsuits, sweaters, specific shoes, waterproof cameras, and other such things. Be sure to ask questions when making your reservation.