Trailhead Direct Just Made Its Last Run to Mount Si. Here's What Changes for the Rest of Fall.

Sunday, August 30 was the last day you could ride a bus from Capitol Hill straight to the Mount Si trailhead for three dollars. King County Metro's Trailhead Direct shuttle, which has run every weekend and a couple of holidays since Memorial Day, wrapped its ninth season that afternoon and won't return until next May. For the next nine months, getting to the trailhead on SE Mount Si Road means a car, a Discover Pass, and whatever spot you can find.

If you hike this mountain regularly, that sentence probably doesn't surprise you. What might is how little the shuttle's absence actually changes for most people who use this trail, and how much the next six weeks matter for the ones who plan around crowds instead of just tolerating them.

What Just Stopped, and What It Didn't

Trailhead Direct is a joint project of King County Metro, King County Parks, and the Seattle Department of Transportation, with Amazon chipping in as a promotional sponsor. The route ran every 30 minutes on weekends and select holidays from May 23 through August 30, connecting Capitol Hill Station to Mount Si, Mount Teneriffe, and Little Si trailheads by way of downtown Seattle and South Bellevue. It's a real service with real riders: since launching in 2017, it has carried more than 89,000 people to trailheads along the I-90 corridor, and last year alone the combined Mount Si and Issaquah Alps routes logged 12,263 riders, a 35 percent jump over 2024.

Here's the part worth sitting with. Twelve thousand riders sounds like a lot until you set it against how many cars fill that trailhead lot on a single good Saturday. The shuttle serves the fraction of hikers who don't drive, mostly people without cars or those making a car-free day of it from Capitol Hill. For everyone else, the ones already circling for parking at 8 a.m., nothing about their Saturday routine just changed. The shuttle's disappearance is a genuine loss for transit-dependent hikers and a non-event for almost everyone driving up SE Mount Si Road.

The Parking Lot Doesn't Know the Season Changed

That parking lot is worth understanding on its own terms, because Labor Day doesn't reset it. The large paved lot at the Mount Si trailhead fills by 8 to 9 a.m. on sunny weekends from May through October, not just during summer. Overflow spots line the road shoulder once it's full, and a Discover Pass is required and actively enforced. None of that changes because the shuttle stopped running. If anything, a clear September Saturday can pull the same crowd as a July one, since Mount Si stays hikeable and scenic well past the point when most people assume hiking season has wound down.

The trail itself reflects that year-round popularity. It's consistently described as one of the busiest hikes in the state, and reviewers who show up expecting solitude on a sunny weekend are usually disappointed. The one variable that reliably thins the crowd isn't the calendar season. It's the day of the week and the hour you start.

The Weekday Window

This is where the September calendar actually works in your favor. A hiker who went up on Thursday, August 27, a weekday, called it not crowded and said they passed only about ten people the entire way, a rare count for a trail this heavily trafficked. Compare that to the standard weekend description: extremely crowded, parking lot full by mid-morning, rarely more than five minutes between passing another hiker. The gap between a Thursday morning and a Saturday morning on this exact trail is the difference between having the switchbacks mostly to yourself and threading through a line of people the whole way up.

Weather cooperates with this plan too. Fall is often described as the best hiking season on this trail, with more stable weather and fewer crowds than summer, even as the days get noticeably shorter once September turns over. Snow and ice above 3,000 feet don't typically show up on Mount Si until November, which means the stretch between now and then is the last real window before the upper switchbacks near Snag Flat and the summit viewpoint at 3,900 feet start requiring traction devices again. After the storms that rolled through earlier this year, volunteer crews including a group nicknamed the "Pi on Si" work party spent weeks clearing blowdown across those same switchbacks, a reminder that this trail stays hikeable because people who use it also maintain it.

Put together: the shuttle is gone, the weekend crowd hasn't moved, and the best window of the year to hike Mount Si without either is right now, on a weekday morning, before the first snow.

If You Want the Views Without the Line

Mount Si isn't the only option inside the Mount Si Natural Resources Conservation Area, and it's worth knowing what else is back there if the main lot is already full when you arrive.

• Little Si shares a trailhead area nearby and is the shorter, gentler climb of the two, with views of the Snoqualmie Valley and Rattlesnake Mountain from the top. It still requires a Discover Pass and still draws a crowd, but its lower elevation gain makes it a faster in-and-out.
• Boulder Garden Loop connects the Little Si and Mount Si trailheads through a rock formation area popular with climbers, and it's a good option if you want a shorter loop without committing to a full summit push.
• Mount Teneriffe is served by the same trailhead cluster and involves a steeper push through switchbacks to a waterfall in the foothills, a solid alternative on days when the Mount Si lot is already full.
• Snoqualmie Valley Trail is the flat, 29.5-mile former railroad grade that runs from Duvall through Carnation, past Snoqualmie Falls, and into North Bend. No permit is required, it's an easier walk or ride through working farmland, and it passes landmarks like Tolt-MacDonald Park, Meadowbrook Farm, and the Tokul Trestle. It's managed by King County Parks and stays open through the fall for anyone who wants river and valley views without an elevation fight.

The Weekend In Town If You'd Rather Skip the Trailhead Entirely

Not every fall weekend needs to end with you circling for parking on a forest service road. The Snoqualmie Street Fair returns to Snoqualmie Ridge on September 12, hosted by the SnoValley Chamber of Commerce, and it's a lower-key way to spend a Saturday without leaving pavement. A few weeks later, the Northwest Railway Museum runs its autumn train excursion out of the Snoqualmie Depot, with cider press demonstrations, live music, and hands-on apple coring built into the two-hour round trip, a genuinely local alternative for the weekends when the mountain feels like more effort than it's worth.

If you do decide to drive up for the trail, the Discover Pass is the one piece of paperwork that trips people up. It's sold at REI, many area grocery stores, ranger stations, and at the DMV for Washington residents, and it's worth buying before you're standing at the trailhead kiosk realizing you forgot.

The season didn't end when the shuttle stopped. It just got quieter, for anyone willing to trade a Saturday for a Tuesday.

If you're the kind of person who plans your weekends around trail conditions and parking lot math, chances are you already know this valley better than most search results ever will. That's exactly the kind of local read Pacific NW Houses brings to every property we help place here, whether it's a Snoqualmie Ridge home five minutes from the trailhead or a quieter lot backing onto the valley trail itself.