This is one of the world's top fisheries, only 1 hour and 15 minutes from Denver, and easily accessible by a hiking trail.
Cheesman Canyon is considered one of the top fisheries in the world, and this stretch of the South Platte River is easily accessed at the Cheesman trailhead off CR 126 just Southwest of Deckers. There are tons of great fishing opportunities along this stretch of the river, but it does tend to get crowded on weekends. This section of the river holds some monster trout, but they are smart so you have to be stealthy.