Southwest Montana contains the best fly fishing on the Jefferson River. Formed by the confluence of the Beaverhead, Big Hole, and Ruby Rivers, the Jefferson can't quite compare to the fabled water of its sources when it comes to spectacular fishing, but the forty miles from Twin Bridges to Cardwell offer relaxing float fishing that can't be found anywhere else. In Southwest Montana, the Jefferson twists and braids through rich hay land. The slow flowing river practically begs to be floated, and the lack of rapids ensures that you'll spend more time fishing, and watching the wildlife and scenery than you will navigating. Although primarily a brown trout fishery, in recent years guides and anglers have been noticing an influx of rainbow trout into the river. Largely because of the proximity to famous trout streams, the Jefferson is underfished, and you might not encounter anyone at all on the river. In addition to fishing, the Jefferson offers very popular floating below Cardwell.