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Orcas Island Marathon

  5.0 ( 2 ) Favorite


25.4 mile 40.8 kilometer loop
83% Runnable


Ascent: 5,415' 1,650 m
Descent: -5,422' -1,653 m
High: 2,374' 724 m
Low: 357' 109 m


Avg Grade: 8% (5°)
Max Grade: 56% (29°)


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Trail shared by Tad Davis

Enjoy beautiful trails with three big climbs and a great view on a clear day.

Tad Davis

Features Lake · River/Creek · Views · Wildlife


This trail race explores Moran State Park's many mountain lakes, wooded singletrack trails, and the 2,409 foot Mount Constitution on Orcas Island in the San Juan Islands of Washington State. On a sunny day the trails offer views of the Cascade Mountain range to the east, surrounding islands, and American and Canadian cities. You can see Mount Baker dominating the skyline with its snow capped top rising out of the Cascades.

A bank of clouds below the rocky cliff as you summit Mt. Constitution and green islands rising through the clouds like rocks in a wild sea make this race one of the most stunning trail half and full marathons in the Pacific Northwest. On the summit, there stands a stone observation tower built by the Civilian Conservation Corps in 1936. The tower offers panoramic views of the sea, islands, mainland, and the Cascades.

Need to Know

Discover Pass required for parking (30$ per year/$10 per day)... ferry reservations recommended... camping limited in off season so get a spot early.


Start with a steady climb and not very technical well-traveled trails for the first 3 miles. Head right at the lake dam (you'll be finishing this first loop coming from the left in another 7 miles) and start a less traveled section of trail with a long downhill and then the first big climb to the top of Mt. Pickett at mile 6 where you come out onto a wide very runnable trail. Head downhill for a little over a mile to a less traveled narrow singletrack around Twin Lakes.

Some more runnable downhill and you'll hit Mountain Lake at mile 9. Hit the beautiful Mountain Lake Loop trail until you connect back to Cascade Falls Trail. Retrace your steps for just over a mile where you'll take a right which will take you to a parking lot. Cross the road and hug the hillside for the next mile or so watching for a Picnic Area sign. This will take you down to the road at Cascade Lake. Take a right past the restroom building and start the long, fairly rocky switchback climb to Cold Springs Trail. Take a left and run a flat beautiful trail for the next 2.5 miles.

Eventually, you'll come to an intersection where you can head straight to Twin Lakes but you'll take the right and start the last big climb to Mount Constitution. Top out on a road and head up it to the tower and overlook for fantastic views on a clear day. Head right from the direction you came and hug the cliff side which will take you back down towards Summit Lake. At about mile 20.5 you'll cross a paved road. Another half mile of running you'll have completed a big loop. Take a left and retrace the big, fairly rocky switchback climb you made earlier. This will take you back down to Cascade Lake Trail where you'll cross the road and head counter clockwise around the lake back to the start.

Run this trail?

We need help with the following missing trail information:

Dogs Allowed, Flora & Fauna, Runner Notes, History & Background


Land Manager: Washington State Parks

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Trail Ratings

  5.0 from 2 votes


  5.0 from 2 votes
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43 Views Last Month
1,592 Since Apr 13, 2015



Gorgeous trail around Cascade Lake.
Apr 13, 2015 near Orcas I…, WA
Nice downhill section after the last of climbs to a paved road crossing.
Apr 13, 2015 near Orcas I…, WA
The view towards Bellingham on the mainland and Mt. Baker on a clear day.
Apr 21, 2015 near Orcas I…, WA
Down the Middle
Apr 22, 2015 near Orcas I…, WA
An Island Lake
Apr 22, 2015 near Orcas I…, WA
Mountain Lake, on the Mountain Lake Loop Trail
Apr 22, 2015 near Orcas I…, WA


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