The Mason Tract Pathway is well marked with blue dots and triangle pathway markers, and along the way there are 12 numbered posts with locator maps, though some might be missing. The trail begins by winding through a sparse stand of pine and then crossing a two-track dirt road with a half mile, moving into a thicker forest on the other side. In another quarter mile, you reach post No. 2 with the loop around Canoe Harbor Campground. Heading east (left), you begin by following a two-track road, then veering off it where a pathway map has been posted. The trail is now skirting the campground and soon dips down to provide the first sight of South Branch.

Here is a classic Michigan trout stream. The river is 20 to 30 yards wide, less than four feet deep in most places, bordered along the banks by sweepers and deadheads, and is crystal clear. The trail follows the river briefly, then at Mile 1.2 from the beginning, comes to the campground's canoe landing, picnic area, and vault toilets. The trail heads southwest, skirts a high bank forested in red pine and hardwoods, and arrives at post No. 3, the return loop to the campground, at Mile 1.4. Located here is a bench, where on a quiet morning you can sit and listen to the river below.

Continuing south (left), the pathway winds over several small hills and swings away from the river to within sight of the dirt access road. It then descends back into view of the South Branch and arrives at post No. 4 in a parking area at Mile 1.8, from which several trails lead to the water's edge. This is the Dogtown access point and marks the spot where market hunters in the 19th century used to gather. Dogtown picked up its name from all the dogs the market hunters used to kill grouse, pheasant, and other wildlife for sale to restaurants in the cities.

For the next half mile, the trail stays within sight of the river as it passes through a pine/beech forest with a thick understory of ferns and then arrives at the Downey's Access Site, another parking area for anglers. Charles Downey was one of the first sportsmen to own the tract after buying the land from an exclusive fishing club of which he was a member. The trail heads southeast from the parking area and in 200 yards arrives in an open, grassy area marked in the middle by post No. 5 at Mile 2.9. Nearby a pair of stone stairways, left over from Downey’s Place, lead down to the river, while just downstream in the water are the rocky remains of an old bridge.

The trail is marked along the grassy bluff with six-foot posts. In another quarter mile, you arrive at another parking area and "Quality Fishing Area." sign that mars a cedar stairway that leads down to the river. Post No. 6 marks the junction to the Thayer Creek Loop and is reached at Mile 3.4. Stay left here, and the pathway re-enters a forest of primarily paper birch, beech, and assorted pine. Most of the time, you are close to the river, but you can't see it until the trail swings past the riverbank at Mile 4 and you get a splendid view upstream. On the other side of the South Branch, but nearly impossible to see, is the Mason Chapel, built in 1960 as a place of reverence for anglers.

The trail swings away from the South Branch, enters a low-lying wet area, and at Mile 3.9 arrives at post No. 7, the return spur of the Thayer Creek Loop just before crossing a bridge over Thayer Creek. After ascending from the creek slightly, the trail merges into an old logging road.

The main trail swings to the southwest (left) from the junction as it follows a logging road briefly, then veers to the left at a well-marked spot. You climb into a small, grassy clearing, re-enter the woods, and eventually emerge at a parking area and access. On the other side of the lot, the trail re-enters the forest and quickly begins skirting the bluffs known to fly fishermen as the High Banks for good reason. The South Branch is far below you, seen every now and then between the towering pines.

At Mile 5.4, the pathway arrives at post No. 8, a prominent hill overlooking the river where there is a bench and a long stairway to the water. The South Branch forms a sharp bend here, and the view from the bench is of flowing water and towering red pines that shade the bluffs. This is the High Banks access site, and from here the trail gradually descends until it cuts across a low-lying wet area and comes to the banks of the South Branch.

The river is briefly followed until the trail arrives at the remains of Durant's Castle at Mile 6. Only parts of a stone foundation and a fireplace are left, but in 1931 this site held a $500,000 home built by the automaker. The 42-room castle was a retreat for Durant, and included a drawing room, music room, library, barber shop, gymnasium, and seven fireplaces. What amused locals the most, though, was a ticker tape that kept the millionaire in contact with the New York stock market even in this getaway in the woods. The house only lasted a year, for it was destroyed by fire in February 1932.

From the ruins, you ascend to a parking area with vault toilets and an interpretive display. A well-built trail leads down to a wooden landing deck on the river for canoeists. The trail resumes in the woods directly across from the covered display sign and resembles a two-track road here. You follow the track through the forest, passing a bench at the edge of a steep bluff. Just beyond, the trail veers off the logging road and ascends into an old clearcut that takes half mile to cross and then arrives at post No. 10 at Mile 7. Stay left at the post and re-enter the woods.

The trail descends to an access to the South Branch and then crosses several low-lying wet areas, some with boardwalks, with the river in view to the south. At Mile 8.6 you arrive at post No. 11 where a spur leads down to the river. The trail levels out in the final mile, staying in the woods and close to Mason Tract Trail, the two-track that anglers use to access many of the access sites on the river. You do pass two more road access points before the final half mile. Finally the traffic on Chase Bridge Road becomes louder with every step and you emerge at the paved road, just north of the bridge and the canoe landing.