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Minnesota State Parks

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Twin Cities - Metro Region
William O''Brien State Park
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16821 O'Brien Trail
North Marine-on-St. Croix, Minnesota   55047

Phone: 651-433-0500
Toll Free: 888-646-6367
Reservations: 866-857-2757
Email: park email button icon
A great "get away" park only one hour from the Twin Cities, William O'Brien provides a beautiful setting for quality recreation along the banks of the St. Croix River. Hiking trails offer quiet exploration of the park's rolling, wooded hills. For anglers, the channels of the St. Croix have northerns, walleye, bass and trout. Ideal for canoeing, the river is also a migratory pathway that offers visitors an exciting diversity of sights and sounds. In the winter, snowshoeing, skiing and camping attract enthusiasts.
Nature of the Area
The variety of vegetation types, the St. Croix River floodplain, oak-hickory forests, scattered white pine areas, marshes, oak savanna, upland prairie and rolling meadows, provides habitat for diverse wildlife populations. Wildflowers give color to the spring woods and the summer fields. One of the best canoeing rivers in the nation, the St.Croix offers pristine scenery just minutes from a major metropolitan area.

Sandstone outcrops formed millions of years ago by inland seas are found along the St. Croix River. Glacial activity played a major role in developing the picturesque valley. As the huge glaciers lumbered south, they scoured the sandstone and deposited soil and rocks of various sizes. As large masses of ice melted, the tremendous volume of released water cut through the soft sandstone, creating the St. Croix River and landscaping the wide, boulder-strewn valley.

Racoon, mink, beaver and woodchucks are prevalent. Upland meadows and woods provide a great environment for white-tail deer and fox. Birdwatchers frequently spot woodpeckers, bluebirds, orioles, herons, raptors and a variety of warblers.
History of the Area
The Dakota and Ojibwe Indians utilized the resources of the valley rich in fur-bearing animals, wild game, and useful plants. In the 1600s, European trappers arrived to engage in the lucrative fur-trade industry. Later, lumberjacks began to harvest the stands of white pine. Sawmills began to dot the St. Croix riverway and the industry flourished in the mid-1800s until the valley was cleared of white pine. William O'Brien, a lumber baron, bought much of the land once owned by the lumber companies. In 1947, his daughter donated 180 acres to be developed as a state park in memory of her father. Over the years, other privately owned pieces of land were added to the park which now totals 1,520 acres.

1. William O'Brien State Park offers a designated swimming beach on Lake Alice.
2. The sandy beach is perfect for sunbathing and building sandcastles.
3. No lifeguards are present, so swim at your own risk.
4. Swimming outside the marked area isn't recommended due to boat traffic and fishing activities.
5. Restrooms and picnic areas are conveniently located near the swimming area for visitors' use.
6. The park does not provide any equipment rentals such as floaties or life jackets.

The park offers a variety of boating options for visitors. Canoe and kayak rentals are available, allowing guests to explore the St. Croix River at their own pace. There's also a boat ramp provided for those who bring their personal watercrafts or motorboats, although there is an enforced no-wake speed limit on this part of the river due to its designation as Wild & Scenic River Area by National Park Service.
Located in Minnesota, the park offers fishing opportunities on Lake Alice and St. Croix River. Species include walleye, northern pike, smallmouth bass and catfish among others.

Boat rentals are available for those interested in lake or river fishing. Ice-fishing is also an option during winter months.

Fishing equipment can be borrowed at no cost from the visitor center if you don't have your own gear.

1. William O'Brien State Park offers numerous picnic spots with tables and grills.
2. Picnic pavilions are available for larger gatherings or events.
3. Enjoy a riverside picnic at the St Croix River's edge, offering stunning views.
4. There is also an enclosed winter warming house perfect for cold-weather picnics.

Biking enthusiasts can explore a 2-mile paved trail, ideal for family rides. Be aware of occasional pedestrians.

For the more adventurous, there's an off-road biking path through hilly terrain. Ensure you're well-equipped and experienced before attempting this route.

Winter offers fat tire biking opportunities on groomed trails but remember to check local weather conditions beforehand as they may be unpredictable.

Always wear helmets while riding and follow park rules for your safety.

Remember that all bike paths are shared with walkers so maintain respectful speeds at all times.
The park offers diverse birding opportunities with over 220 species recorded. It's a popular spot for migratory birds. Birdwatchers can explore various habitats including wetlands, hardwood forests and prairies. The visitor center provides binoculars and field guides for use within the park boundaries.

Visitor Comments, Memories and Reviews
August 14 Awesome by Melissa
park review stars; one to five Great Interpretive Programs and the park staff was amazing. They were full of information and it was all correct. Thanks for a fun time. I highly recommend visiting this park.
April 17 Rude park employees by Rich
park review stars; one to five We were treated rudely and talked down to by a park employee.
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Area Campgrounds
Wildwood Campground
20020 Lake Boulevard
Shafer, MN
Nearby Hotels

The park is located 12 miles north of Stillwater on State Highway 95, near the town of Marine-on-St. Croix.

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Minnesota State Parks