Mount Si climbs 3,150 feet in 8 miles, and a fall weekday is when it finally feels like a mountain
Mount Si doesn’t do subtle. The trail starts switchbacking almost right away, and it keeps climbing until you’ve gained about 3,150 feet.
It’s roughly 8 miles round trip near North Bend, and around 100,000 people hike it each year. A fall weekday is when it stops feeling like a parking-lot lottery and starts feeling like a mountain.
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What the climb asks of you
Plan on about 8 miles round trip and around 3,150 feet of elevation gain, which Washington Trails Association rates as hard. That’s a full-day effort for most people, not a quick lap before brunch.
The first stretch climbs steadily through forest, then flattens out through Snag Flat, an old-growth stand that has survived both fire and logging. Past that, the trail gets steeper through younger trees, and your legs will have opinions.
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The payoff at the top
Near the top, stone steps lead past the lunch spot to an overlook above the Snoqualmie Valley, with Seattle and the Olympics out on the horizon. From the talus slope at the main turnaround, Mount Rainier dominates the skyline on a clear day.
My one firm opinion: pick a clear weekday and start early. That’s a lot of climbing to spend on a gray wall of cloud, and the lot often overflows on nice days, which is exactly why weekends are the hard sell.
What about the Haystack?
Mount Si’s true summit is the Haystack, and WTA describes the way up as a rough scramble from the other branch of the trail. Plenty of hikers stop at its base, and that’s a great place to eat lunch.
If the top is calling you, read the current trail guidance from Washington Trails Association first. A scramble is not the place to wing it.
Before you go
Parking at the trailhead takes a Discover Pass, and dogs are allowed on leash. Daylight is shorter this time of year, so start early and toss a headlamp in your pack.
The trailhead sits off I-90 at exit 32, close to North Bend. So will you stop at the overlook, or are you eyeing that Haystack scramble?
Trip tips: grab a rental car to get out here, and lock in your hotel before the good rooms are gone.
Rules and fees change, so always confirm current requirements before you go.
