The Au Sable River is considered one of the best trout fisheries east of the Rockies and has been designated a blue ribbon trout stream by the Michigan Department of Natural Resources. The Au Sable runs 138 miles through the northern lower peninsula through the towns of Grayling and Mio and enters Lake Huron at Oscoda. The Au Sable watershed is made up of several major tributaries. They include the South Branch Au Sable, North Branch Au Sable,  East Branch Au Sable, as well as two tributaries of Big Creek.  

Starting north of Grayling, the Au Sable River turns east and gathers the flow of the East Branch at the town of Grayling. A few miles east of Grayling the river flows past Burton's Landing, which is the start of the fly fishing only, catch-and-release section commonly known as the "Holy Water." This area extends for nearly nine miles downstream to Wakeley Bridge. Within this stretch, the river consists mainly of sand and gravel. Beautiful trout filled pools, runs, and riffles dominate this stretch of water. This section is also known for some very legendary homes and lodges including the George Griffith's Barbless Hook.

Several access points are available for anglers to wade or float from. Thendara Road and Stephan Bridge are a couple of the many areas with good access. The water is relatively large but easy to navigate and wade.

The water from Wakeley Bridge to Mio Pond easily equals the quality of the water from Grayling to Wakeley Bridge. The water is larger and has more deep pools and runs for large trout to hide. Wading here can be difficult in some areas, and caution needs to be taken. Prolific hatches exist here and throughout the rest of the river. Hexagenia Limbata also known as "Michigan Caddis" is a very famous and large mayfly that are prolific in this area. Large brown trout (twenty plus inches) are found feeding to this mayfly and are sometimes caught during this hatch. Many "old-timers" will often be seen "sneaking" around the river during this hatch looking for that trophy brown. A couple of good access points are found at The Whirlpool off of Cherry Creek Road and at Parmalee Bridge.

From Mio Dam to McKinley Bridge the river harbors an abundance of trophy size trout. Large brown and rainbow trout are in good numbers here. Like the upper areas, quality hatches make it an excellent stretch. The water is deep and strong in many sectors. Wading is a challenge although it can be accomplished in certain areas. A boat is the best way to cover and fish this water. Hiring a guide will ensure the most potential out of this great section of the river. A few good access points are located at Perry Creek, Comins Flats, and Mckinley Bridge.

The North and South Branches of the Au Sable are also great fisheries. They provide excellent angling with plenty of easily waded water. The South Branch flows northerly out of Houghton Lake towards the Mainstream of the Au Sable passing the town of Roscommon on its way. It meets the mainstream a short distance below Wakeley Bridge. A section for fishing with artificial flies only, no kill is located from Chase Bridge downstream to Lower High Banks. Brook, brown and some rainbow trout can be found in its waters. Access areas are numerous along the river providing ideal areas to "hop" out of your car and wade fish. The North Branch flows southeasterly passing through Lovells eventually emptying into the Mainstream a few miles downstream from the South Branch. The North Branch is also a quality fishery with a section devoted to fishing with artificial flies only from Sheep Ranch downstream to the confluence with the Mainstream. This is a beautiful river with slick pools and quality trout. It is a great dry fly fishery like the rest of the upper Au Sable River system. Access can be gained in many areas along the North Branch's path.

The lower Au Sable River from Foote Dam to Lake Huron is a quality steelhead fishery. The river here is vast and by some standards dangerous. Careful wading is a must, and a boat provides the best angling. Steelhead and salmon both migrate up this section of the river and can be caught in the same manner as the other great lake tributaries. Steelhead fishing is available (depending upon conditions) from late fall through early spring.

The Au Sable River is an awesome fishery. Trophy brown trout, "screaming" rainbows, beautiful brook trout, and acrobatic steelhead are caught in good numbers each year. Hatches are extremely prolific and will challenge those of the Delaware River in New York State. Anglers come to this river for more than just its great angling as it is also a beautiful and serene river. The Michigan woods is home to a diversity of wildlife from hawks and eagles to deer and bear.