Lake Stevens Monster

Updated June 11, 2025

# Lake Stevens Monster (Glacial Erratic), Washington: What It Is, Why It Matters, and How to Visit Respectfully

The “Lake Stevens Monster” isn’t a statue or a themed roadside creature. It’s a massive glacial erratic—a boulder transported by ice and left behind when glaciers retreated—tucked into a small neighborhood park in Lake Stevens, Washington. Geology Field Trips

What makes it remarkable is scale. Geologist Dave Tucker reports measurements of about 34 feet (10.36 m) tall, about 78 feet (23.77 m) long, and about 210 feet (64 m) in circumference, calling it the largest known measured erratic in Washington, and possibly among the largest in the United States (the “U.S.” comparison is framed as “may be,” not a settled fact). Geology Field Trips

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## What you’re looking at: a “visitor from the Ice Age”

A glacial erratic is a rock that’s geologically “out of place” compared with the surrounding area because it was carried by moving ice. In the Puget Lowland, that story ties to the Vashon glaciation (part of the last glacial period in the region). Tucker notes the Lake Stevens erratic was likely carried within the Vashon glacier flowing out of British Columbia into the Puget Basin. Geology Field Trips

HistoryLink describes the Monster as an “Ice Age” relic and repeats the same headline measurements (34 ft tall, 78 ft long, 210 ft circumference), emphasizing how unusual it is to find something of that size sitting in a modern subdivision landscape.

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## Geology details that most casual write-ups skip

Tucker describes the boulder as (somewhat) serpentinized greenstone. In plain terms:

– Greenstone forms when basalt lava undergoes low-grade metamorphism (mineral changes due to heat/pressure without fully melting). Geology Field Trips
– The basalt originally erupted on an ancient seafloor and later got caught up in tectonic processes along the Pacific Northwest margin. Geology Field Trips
– Serpentinization (formation of serpentine minerals) is associated with deformation/shearing—plausible in rocks caught between tectonic plates. Geology Field Trips

That’s the hidden value of this stop: it’s not “just a big rock.” It’s a physical clue that links plate tectonics, seafloor volcanism, metamorphism, and glaciation in one place. Geology Field Trips

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## Where it is (and how to get there using verified directions)

NWGeology places the erratic in Lake Stevens, Washington, described as southeast of Marysville and east of Everett, “hidden among the bushes” within a subdivision, in a tiny park maintained by the neighborhood. Geology Field Trips

Verified driving approach (from NWGeology):
From I-5 in Everett, head east on US-2 for ~2 miles, take the 20th Street exit, continue about a mile to the stoplight at 83rd Ave, turn left (north), and follow it to the end. Geology Field Trips

Verified coordinates:
NWGeology gives the lat/long as 47° 59.816’ N, 122° 6.954’ W (which corresponds closely to ~47.9969, -122.1159). Geology Field Trips

On-foot access (what’s confirmed):
NWGeology states there’s an informal trail that loops around to the “dark, looming east face.” Geology Field Trips

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## What to expect on site

### The scale is not obvious from one angle
NWGeology notes that trees, brush, and the slope can make it hard to get perspective, especially from the “street side,” and that the taller face is better appreciated by walking around. Geology Field Trips

### You may see broken fragments nearby
Rock fragments are reported on the ground on the east side, useful for seeing a fresh surface—along with an explicit “no hammers” request. Geology Field Trips

### This is a neighborhood setting
Both NWGeology and HistoryLink emphasize its placement within/adjacent to a residential subdivision rather than a formal state park or big interpretive site. Geology Field Trips

Practical implication: treat it like you’re visiting a quiet pocket park—keep voices low, don’t block driveways, and stay on the visible paths where possible.

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## Pair it with another Lake Stevens stop (easy internal link opportunity)

If you’re building a Lake Stevens-area cluster page, Lundeen Park is a clean companion stop because it’s directly tied to the lake experience: the RealJourneyTravels listing highlights sandy beach access to Lake Stevens plus typical park amenities (playground, courts, grills, etc.). Journey Travels

– Internal link idea 1: Lundeen Park (RealJourneyTravels place page) Journey Travels
– Internal link idea 2: If you want a broader “nearby lakes/parks” tie-in within Snohomish County, Martha Lake Park is another RealJourneyTravels place page you already have. Journey Travels

(Those are on-site internal links that can sit naturally in a “Nearby stops” section without inventing any URLs beyond pages that already exist.)

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## Accuracy notes and what may be outdated

– Measurements & “largest” claims: The detailed measurements and comparisons in NWGeology were published in 2011, and the “largest in the U.S.” framing is explicitly uncertain (“may be”). Treat “largest in Washington (measured)” as the stronger claim, and avoid presenting “largest in the U.S.” as settled. Geology Field Trips
– Access conditions can change: NWGeology describes a neighborhood-maintained pocket park and an informal trail. That’s not the same as a formally managed public trail system, so conditions and signage can change over time. Geology Field Trips

If you want this article to stay evergreen, a simple editorial policy works: revisit any “getting there” details annually and update if street routing or access changes.

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## Quick fact sheet (all source-backed)

– Type: Glacial erratic Geology Field Trips
– Material: (Somewhat) serpentinized greenstone Geology Field Trips
– Reported size: ~34 ft tall; ~78 ft long; ~210 ft circumference Geology Field Trips
– Setting: Small neighborhood park / subdivision context Geology Field Trips
– Coordinates: 47° 59.816’ N, 122° 6.954’ W Geology Field Trips

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