General Info: Next to Montana, Colorado is easily the most popular state for fly fishing, and there is good reason for that. Countless streams and rivers hold huge numbers of healthy trout in every corner of the state. This is a bucket-list state. Every dedicated angler should have Colorado on their radar. Whether you want to stalk fish in a small creek, float a big river in a drift boat, or backpack to remote mountain lakes, Colorado is one of the best places anywhere to chase trout.