The Colorado River is the largest river in the state and is known for holding a lot of trout. The upper river is easily wadeable and holds both rainbows and browns. The lower river is better fished from a drift boat and can hold some large fish. In the spring the rainbows run into the river's tributaries and some big fish can be found. Some prime stretches are on the Roaring Fork, Eagle and the Williams Fork. Summer is dry fly season and the fish will eagerly take dries off the top. Fall is the best time to target trophy browns, with large streamers being the favorite flies.