Washington County, Minnesota · Est. 1839
Marine on St. Croix
A riverside village founded in 1839 around Minnesota's first commercial sawmill — today a quiet place of stone buildings, oak savanna and one of the cleanest big rivers in the Midwest.
Photo: McGhiever / CC BY-SA 4.0, via Wikimedia Commons
Marine on St. Croix sits on a bend of the St. Croix River in Washington County, about forty minutes from downtown St. Paul. It is small — 664 people at the 2020 census — but the whole village center is a National Register historic district, and it backs onto one of Minnesota’s best-loved state parks.
This guide pulls together everything a visitor or neighbor actually needs in one place: what the river is doing today, what the weather is normally like in the month you’re planning, where to park and paddle, which wildflowers and birds you’re likely to see, what’s on the city calendar, and the story of how a lumber camp became one of the best-preserved river towns in the Upper Midwest.
The numbers on these pages are not copied from anywhere. They are calculated from public data — U.S. Geological Survey river gauges going back to 1903, thirty years of daily weather, tens of thousands of wildlife records, census tables and OpenStreetMap — and refreshed every time the site is rebuilt. The writing is our own. See where the data comes from.
Start exploring
All things to do →
State park
William O'Brien State Park
1,520 acres of river bottom, oak savanna and wooded bluffs two miles north of the village — camping, a swimming beach on Lake Alice, and miles of ski trails.
On the water
Paddle the St. Croix
A slow, wide, sandy-bottomed stretch of a National Scenic Riverway. How to plan a trip, where to launch, and how to read today's flow.
History
Marine Mill Historic Site
Stone footings of the first commercial sawmill in Minnesota, on a bluff path above the river. Free, open year-round, a five-minute walk from the general store.
Self-guided walk
Historic walking tour
An hour-long loop past the 1870 general store, the 1872 Stone House, the 1888 Village Hall and the mill ruins — with a map and the story behind each stop.
Trails
Hiking & cross-country skiing
River-level trails, savanna loops and bluff-top overlooks. Which trail to pick for a 30-minute stroll, a long hike or a winter ski.
On the water
Fishing the St. Croix
Smallmouth bass, walleye and northern pike in a clean, rocky river — plus a fishing pier on Lake Alice for kids.
Right now in October
What October looks like here
In October, Marine on St. Croix averages a high of 57°F and a low of 43°F. Expect about 2.9 in of precipitation (liquid equivalent) and roughly 1 in of snow. About 3 nights dip to freezing. Days last about 10.9 hours, with roughly 7.2 hours of sunshine.
Good for: Hiking, Mushrooms.
The river, by the numbers
River dashboard →At 1,590 cubic feet per second, the St. Croix at St. Croix Falls is running much below normal for October 1. Flow on this date has been lower 10% of the time in 124 years of records; the typical (median) flow is 2,550 cfs.
Blue line: daily mean flow. Shaded band: the middle 50% of flows recorded on each date since 1903 (USGS).
Wild neighbors
Nature guide →
History
Minnesota's lumber industry started here
In August 1839 a water-powered sawmill began cutting St. Croix white pine at Marine Mills — the first commercial sawmill in what would become Minnesota. The mill's stone footings still sit beside the river, a short walk from a general store (1870), a stone meeting house (1872) and a village hall (1888) that still hosts city council meetings.
The population peaked at 689 in 2010, fell to 297 by 1930 after the pine ran out, and has only recently climbed back.
Coming up
All events →- Heavy Metal DaySaturday, 9:00 AM · Behind Security
From the river valley
Community →- Science Museum of Minnesota permanently protects 130 acres along the St. Croix RiverSt. Croix 360 · Sep 24, 2026
- St. Croix Valley Foundation awards record $442,200 in environmental grantsSt. Croix 360 · Aug 28, 2026
- Part 3: ‘Girl Reporter’ goes canoeing on the St. Croix River in 1921St. Croix 360 · Aug 14, 2026
- Part 2: ‘Girl Reporter’ goes canoeing on the St. Croix River in 1921St. Croix 360 · Aug 7, 2026
- Minnesota’s ‘Girl Reporter’ wrote of St. Croix River canoeing years before befriending Eleanor RooseveltSt. Croix 360 · Jul 31, 2026