31.3
PDI
12.7 mi
DISTANCE
4,674 ft
GAINED
7 %
AVG. GRADE
FULL CLIMB STATS
Page Contributor(s): Bryant Robbins and Jill Aho, Palmer, AK, USA; Travis Profit; Don Baty, Corvallis, OR
INTRO
Slate Peak holds the title of the highest road in Washington. Past Hart's Pass, a spur climbs to a decommissioned fire lookout at 7,488 feet - the highest point in the state reachable by vehicle, bike included. Our measured climb covers 12.7 miles and 4,674 feet of gain at an average 7% grade, starting near Mazama in the Methow Valley and finishing just below the lookout at 7,220 feet, and currently ranks 38th on our worldwide difficulty list.
The road itself is part of the story. Hart's Pass Road was blasted into the mountainside in 1893 to serve gold and silver mines that once supported over 1,000 residents; today it's a narrow, cliff-hugging route into the Pasayten Wilderness with sweeping views of the North Cascades. The first several miles out of Mazama are paved, but the climb turns to gravel and washboard well before Hart's Pass and stays that way to the summit - bring the tire clearance to match.
As of August 2026, this climb is not currently rideable to the top: the U.S. Forest Service has closed Forest Road 5400 from the Monument Creek Trailhead to its end - covering both Hart's Pass and Slate Peak - under a wildfire-safety closure order tied to the Ptarmigan Fire, in effect through October 30, 2026. Even outside of closures like this one, the road only opens for a few months a year, typically July through early fall, before snow shuts it down again.
PLAN YOUR ROUTE
We've partnered with Sherpa-Map.com to bring you the best route planning tool. With a PRO Membership you can use this climb as a reference when creating your route. At 6.98% average over 12.7 miles, Slate Peak is a steady grind rather than a spiky one, but it's a long grind at altitude. The lower miles out of Mazama are the gentlest part of the climb - the paved approach toward Yellowjacket Sno-Park is only mildly graded. Past Yellowjacket, the road turns to gravel and the climbing gets more sustained on the way up to Hart's Pass, around 6,200 feet, before continuing past the pass to the final pitches below the Slate Peak lookout at 7,220+ feet.
Expect the surface itself - loose gravel and washboard that reportedly varies year to year depending on how hard the previous winter was - to affect your effective effort as much as the gradient does.
Roadway: Slate Peak Road (Forest Road 5400, the continuation of Hart's Pass Road) is paved for roughly the first six miles out of Mazama, then turns to unpaved forest road - gravel and washboard, with rough patches that vary from year to year - the rest of the way to Hart's Pass and on to the Slate Peak lookout. As of August 2026, the road is closed to travel from the Monument Creek Trailhead junction to its end, covering Hart's Pass and Slate Peak, under a U.S. Forest Service wildfire-safety order tied to the Ptarmigan Fire, in effect through October 30, 2026 - check current Forest Service alerts for the Methow Valley Ranger District before planning a trip. The road is also only open seasonally in any given year, typically opening in July as snow clears and closing again with the first fall snowfall.
Traffic: This is a narrow, remote forest road with light but real traffic - mostly other recreational vehicles, hikers headed for Pacific Crest Trail access points, and occasional Forest Service vehicles. There are steep drop-offs and blind corners in places, so ride defensively even though volumes are low.
Parking: Most riders start at the Mazama store, which has parking along with food and a sandwich bar. An alternative is to drive partway up Lost River Road to Yellowjacket Sno-Park, cutting about 6.1 miles - almost all paved - off the route. Monument Creek Trailhead, a dirt pullout a bit further up the road, is a third option.
This is a remote, high-altitude ride with real gaps in services - the nearest reliable gas is in Winthrop, about 14 miles east, or Marblemount, 75 miles west; the Mazama store reportedly sometimes has gas but has been out on more than one visit. Carry all the food and water you'll need, since there's nothing past the store once you start climbing.
Given the gravel surface for most of the route, use tires with real volume and tread rather than a standard road setup. Conditions at 7,000+ feet can swing fast - pack layers for wind and cold even on a warm day in the valley, and check current road and weather status before you go given both the seasonal closure and the wildfire-related closure noted above.
Before heading out on any cycling adventure check out our Things to Bring on a Cycling Trip and use our interactive check list to ensure you don't forget anything.
Mazama and Winthrop are the two lodging bases. Winthrop, about 14 miles from the start, has a handful of motels and full town services; Mazama is much smaller, with an inn next to the general store and limited additional options, so book ahead in season.
Before planning a trip here, check the current status of Forest Road 5400 with the Methow Valley Ranger District - as of August 2026 the road is closed above Monument Creek Trailhead (covering Hart's Pass and Slate Peak) under a wildfire-safety order through October 30, 2026, on top of its normal winter closure. This is a climb worth timing carefully rather than showing up and hoping.
ROUTE MAP
MEMBER RATING
CURRENT WEATHER
PJAMM TRIPS ADVENTURE STARTER BUNDLES
Check out PJAMM Adventure's prepackaged (self-guided) cycling trips. They will help you plan, document and conquer your next adventure.
NEARBY CLIMBS (0) RADIAL PROXIMITY
FROM No Climbs Found
MEMBER REVIEWS & COMMENTS
Let us know what you thought of this climb. Signup for our FREE membership to write a review or post a comment.
Already have an account?
LOG IN HERE
benguernsey
Did this climb in 2021, very long and difficult with a great pay off at the top with views of mountains upon mountains looking from the North Cascades into Canada. IMO under ranked with the surface quality and finishes steep.
