The Tam McArthur Rim trail is brutal but extremely rewarding. The 5.5 mile trail (round trip) gets its name from a mountainous wall, or rim, that forms a picturesque backdrop for 3 Creeks Lake. The rim was named after “Tam” Lewis A. McArthur who served on the Oregon Geographic Board.
To get to the Tam Mcarthur Rim trailhead head east on Highway 126 (you can go up the Highway 242 scenic route too) until you reach Sisters Oregon. When you reach Sisters take a right (south) on Elm Street. Follow this about 17 miles, the last 2-miles being gravel, until you reach a pair of latrines on the left-hand side of the road. Shortly after the latrines you will see signage and a trailhead. You can park on the side of the road. If you begin to drive by 3 Creeks Lake you’ve gone to far.
The trail is dusty, sandy, stoney, gravely, snowy, and gains close to 1,300-feet in elevation, so it’s important to bring a good pair of hiking shoes on this hike. Sun screen, chapstick, food, and plenty of water are also essential for this hike.
Looking up towards the Tam McArthur Rim (TMR) can make this trail seem a little daunting, but if you keep hiking you will be up on the TMR before you know it. The trail is steepest at the beginning, and it switchbacks through ponderosa forests until you are on the (TMR). Once you reach the TMR the forest opens up and the trail becomes relatively flat with a few steep hills. You will also encounter a number of snow patches depending on how long the snow lingers. While you hike along the rim you can expect a clear view of Mt. Bachelor and an steep and rocky view of the TMR from above and 3 Creeks Lake.
After following the TMR the trail heads east towards Broken Top. You can expect more snow patches and one last steep push to the top of the trail. The trail ends on a ridgeline facing Broken Top. There are a few good sitting rocks where you can relax, eat lunch, and soak up the scenery. From the north to the south you can see Mt. Hood, Mt. Jefferson, 3 Fingered Jack, Mt. Washington, the Three Sisters (from north to south they are named Faith, Hope, and Charity), Broken Top (directly east), and Mt. Bachelor to the south.
I didn’t see hardly any wildlife along the trail other than few magpies. The bugs weren’t bad either. I only saw a few flies and one mosquito (it bit me).
After a rough hike like this its important to treat yourself. I recommend a soak in the 3 Creeks Lake. After spending 5-hours on the trail, I was dirty, grimy, and tired. 3 Creeks Lake is great for swimming; it has sandy beaches and cool-clear water. After swimming in the lake for half an hour I felt fresh and rejuvenated. There is also a store on the lake front that sells ice cream, candy and a few random items like chapstick. You can also rent a boat at this store.