I haven't heard of too many folks doing this loop but this is a spectacular run. It is also a very long day. You'll have slow going through the sand sections and over a couple of passes but you will be rewarded with breathtaking scenery and a wide variety of trail conditions. Put this run on your calendar.
Meadow near Moraine Lake south of South Sister
When To Do This Run
Much of the trail around sisters is at 6000 feet and it seem to retain snow longer than other places in Oregon. The season is probably from Mid July through September. I'd suggest checking with a ranger before heading out to get the latest conditions. If you run in September you better be real fast or bring a good flashlight.
General Route Information
This loop is 43.7 miles long. The starting point for this run is north of North Sister at Lava Camp Lake trailhead off of HWY 242. From there you run down 2.6 miles to Scott pass and take a left on Scott trail (trail 4068). After a few miles you take a right and head down the east side of the Sisters all the Way to Green Lakes. From there you head south and west, crossing the climbing route for South Sister and then head up North west to connect with the PCT. You then head north on the PCT until you get back to your car.
I'm providing directions for running this loop clockwise. There are two reasons for this. First the east side, while scenic, isn't quite as scenic as the west side and I'd rather cover that when I'm strong. Hopefully the beautiful scenery on the west side will distract you when you are tired. Secondly, if you run CW then somewhere after green lakes you pick up the PCT and stay on the that trail for 19 miles to the finish. When I get tired (or when it is dark) I'd prefer to just stick with one trail and not deal with route finding.
For the most part, this run is pretty straight-forward. Of course you need to bring a map but most of the trail intersections are clearly marked and route finding isn't terribly difficult. Water supplies are adequate as well. You can generally expect to find a creek every 10 miles or less. On the east side a few of the streams are silty but there are more streams to choose from.
The trail itself is in good condition. A few sections are sandy and you'll have trouble running through that but most of the trail is in excellent conditions. The trail is generally rolling with two big climbs. One on the south side just before Green Lakes and one on the west side at Dilldock pass I haven't done this run with an altimeter watch but I'd put the cumulative elevation gain at under 6000 feet.
Maps and Reference Information
This is going to be a long day. Make sure you bring your 10 Essentials along.
You need to bring a map for this run. Unfortunately, Green Trails hasn't come out with a map for this area yet. Instead you'll need to take along the Three Sisters Wilderness Map. This is a great map with all the trails clearly marked, the only disadvantage is that it is somewhat bulky. This map is available at REI.
In addition to the above map there are couple of books with good descriptions for this route. Backpacking OREGON has a good description of this route with background information and a number of alternative side trips listed. I also used Hiking Oregon's Central Cascades from FalconGuide for some of the milage information (this book also has a rough contour map for the route).
It's a good idea to check with the ranger before heading up to find out if there are any trail closures or other info. The McKenzie Ranger Station appears to be the best bet 541.822.3381. You may also want to check out the Deschutes National Forest at 541.383.5300
Mileage Splits and Time Estimate
The table below gives split distances for the run.
Sisters Loop Mileage
This run is going to take a while, I'd plan on being out for 12-14 hours (much much longer if you are not an experienced ultrarunner).
Take HWY 5 South out of Portland.
At Eugene, take HWY 126 East
Stay on 126 through Blue River and McKenzie Bridge
After McKenzie Bridge take a right onto HWY 242 (Old McKenzie Hwy)
Stay on Hwy 242 for 21 miles as you wind your way up to McKenzie pass
The Lava Lakes Trailhead is on the right a few miles beyond the Obsidian trailhead.
This may not be the fastest way to the trailhead but it works. From Portland plan on driving about 3.5 hours. To park at the Trailhead you must have a Northwest Forest Pass.
I haven't done this run as a one day run but I did do it as a fastpack in August of 2003. Listed below are the photos from that rip.
For each picture, you can click on the picture to bring up a large full resolution shot (but this may take a while to load).