Mount Si Trail

Difficulty
This reflects the 10Adventures difficulty rating for each route. We aim to keep ratings consistent across regions.
Hard
Duration
This reflects the estimated time the majority of users will take on this trail. If you are slower, add time to the top-end figure. If you are fast, then you may complete this route faster than this time range.
5-7h
Distance
This reflects the return distance of this route as measured by the GPS file.
12.1 km
Elevation
This reflects the total elevation gained throughout this route as measured by the GPS file. This includes all ascents and descents, and is higher than what is quoted in most route guides, which simply measure the distance between the starting-point and high-point of the route.
1,017 m
User Ratings
These ratings are completed by users who have completed this trail and not subject to reviews by 10Adventures.
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Directions to Trailhead

The Mount Si Trail is a 12.1 km out and back trail that sees heavy traffic and is rated as hard. This hike is completed by upwards of 100,000 people per year, partly because of its proximity to Seattle and partly because of its wild beauty. On a trail this well-used, exercising good trail etiquette is essential.

The hike itself is fairly demanding, not just for the elevation or length, but because of the Haystack, a scramble that leads to the mountain’s true summit. While it’s worthwhile to climb the Haystack if you feel comfortable doing so, many hikers enjoy the great views just below the true summit, making this a somewhat easier hike.

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Route Description for Mount Si Trail

A truly staggering number of people hike Mount Si Trail every year, and for good reason- it’s beautiful, and it’s reasonably close to Seattle. This hike is a solid workout, gaining 945 m in just under 6.4 km. It’s enough of a challenge for stronger hikers, but many novice hikers choose Mount Si as their first “hard” hike. Very experienced hikers often bring weighted packs to Mount Si to train for their ascents of Mount Rainier. It’s said that if they can reach the summit in less than 2 hours, they’re ready for Rainier.

Some hikers stop just below the true summit, known as the Haystack. Climbing the Haystack is very possible, but just involves some hands-on scrambling, which may or may not entice all hikers. That’s fine! The views from below are still spectacular.

The trail begins from the parking lot, immediately launching into switchbacks. The ascent is more gentle initially and even flattens out near Snag Flat, a group of old-growth trees. Take a moment to appreciate these trees, even if you’re eager to make good time.

The trail becomes steeper after Snag Flat, and you’ll likely start huffing and puffing. Take a breather at the break in the trees about 3.5 miles in.

Continue climbing, taking on a short, very steep section before reaching a talus slope about a 0.4 km past the lookout. The view to the southeast is amazing, and Mount Rainier stands proud in the distance. Some hikers call it a day here, and if you’re not out to conquer the whole mountain, this is a good spot to turn around.

If you ARE out to conquer the mountain, keep going. Take the stone steps to your right, ducking back into the forest before emerging to another great view. You’ll be able to see the Snoqualmie Valley, the Olympics, and Seattle from here.

From this spot, you’ll be able to see the Haystack and the lower false summit. You can either soak up the views from the lower summit or take the scramble up to the top of the true summit. Take care on the way down.

Once you’re ready, retrace your steps, taking care with your footing on the steep sections and remembering to yield to uphill traffic as you descend.

Hiking Route Highlights

Mount Rainier

The tallest mountain in the state is a dominant part of your view on the Mount Si Trail. This 14,409-foot stratovolcano is an iconic sight and the highlight of your view while hiking this route.

Frequently Asked Questions

Can you hike Mount Si in the winter?

Yes, this hike can be completed year-round. There is no significant avalanche risk on the mountain, but the steep trail may become slippery in cold conditions. Enjoy the winter solitude!

Is Mount Si Twin Peaks?

Yes! Mount Si is the twin peak in Twin Peaks.

What pass do I need for Mount Si?

Please have your Discover Pass ready for this hike.

Insider Hints for Mount Si Trail

  • You can take the Trailhead Direct bus from Seattle to Mount Si to avoid issues with parking.
  • This trail is well-maintained, but you should still work to mitigate the effects of heavy foot traffic. Pack out what you pack in and try to stay on the trail to cut down on erosion and damage to the foliage beside the trail.
  • You’re quite likely to meet some mountain goats on this hike! Keep a respectful distance while you admire them.

Getting to the Mount Si Trail Trailhead

The trailhead for the Mount Si Trail is located on SE Mt. Si Road, 3.9 km past the turn onto the road. The trailhead is on your left.

Route Information

  • Backcountry Campground

    No

  • When to do

    May-October

  • Pets allowed

    Yes - On Leash

  • Family friendly

    No

  • Route Signage

    Average

  • Crowd Levels

    High

  • Route Type

    Out and back

Mount Si Trail Elevation Graph

Weather Forecast

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Mount Si Trail Reviews

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