Top things to do at William O’Brien State Park in Minnesota

One of the closest state parks to the Twin Cities, William O’Brien State Park in Marine of St. Croix is a perfect day trip from Minneapolis and St. Paul, MN. Hike under 100-year-old pine trees, next to the St. Croix River and wetlands, through prairies, oak savanna, and hardwood forests. Other highlights include a huge beaver lodge and a small lake with a sandy beach and fishing pier.   

See my related Minnesota state park series.

• Take the Minnesota State Park Challenge – list of all the best MN state parks with reviews
• How to hike all 66 Minnesota state parks in a year
• Explore Minnesota State Parks on Free State Park Day (updated with 2023 dates)
• Top Minnesota state parks with waterfalls – ranked!

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Top 10 things to do at William O’Brien State Park in Marine of St. Croix, MN

Here are the top 10 things to do at William O’Brien State Park in Marine of St. Croix, Minnesota.

1. Hike under 100-year-old pine trees.
2. Walk through 100 acres of prairie landscapes.
3. Rent a canoe, kayak, or paddleboard on the St. Croix River.
4. Go swimming at the sandy beach in Alice Lake.
5. Fish from the lake’s fishing pier or riverbank.
6. Learn about the area’s history in the visitor center with interpretative exhibits.
7. Camp at the large campground – traditional tent or RV. Four group camps and four cabin campers also available.
8. Look for ancient sandstone outcrops, other geological formations, and migratory birds.
9. Reserve the picnic shelter or claim any of the picnic tables.
10. Winter fans can hike, cross-country ski, skate-ski, snowshoe, or camp at William O’Brien State Park.

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Frequently asked questions about William O’Brien State Park in Marine of St. Croix, Minnesota

Where is William O’Brien State Park located? What is the address for William O’Brien State Park?

William O’Brien State Park is located at 16821 O’Brien Trail, Marine of St. Croix, MN 55047. However, this state park is also near Scandia, Minnesota.

When is William O’Brien State Park open?

William O’Brien State Park is open year-round, 8 a.m. to 10 p.m. every day.

Is William O’Brien State Park free? How much is the admission fee at William O’Brien State Park?

William O’Brien State Park in Minnesota only costs $7 per vehicle per day ($5 per motorcycle). That includes unlimited visits to all Minnesota state parks on the same day. I highly recommend an annual pass, which gives you entrance to all Minnesota state parks. See the Minnesota DNR website for more information. And it’s highly recommended to pay online ahead of time. Minnesota state parks are no longer accepting cash self-payment envelopes on site.

Admission to every Minnesota state park is free for all Minnesota state tribal members.

You can also visit William O’Brien State Park on any of the four free state park days in Minnesota. See my related post for this year’s free state park days.

Does William O’Brien State Park have a lake, river, or waterfall?

Yes. William O’Brien State Park is located adjacent to the St. Croix River. Additionally, you’ll find Alice Lake here as well.

Can you fish at William O’Brien State Park in Minnesota?

Yes. Common fish found in the channels of the St. Croix River at William O’Brien State Park include northerns, walleye, bass, and trout.

Does William O’Brien State Park have a swimming beach?

Yes. William O’Brien State Park features a small, sandy swimming beach on Alice Lake. You can also see the fishing pier in the distance. Note that no lifeguard is on duty at William O’Brien State Park.

Can you boat at William O’Brien State Park? Does William O’Brien State Park offer a boat ramp with trailer access?

Yes. The St. Croix River at William O’Brien State Park is a popular destination for boats, canoes, kayaks and paddleboards. You can rent canoes, kayaks, and paddleboards at the William O’Brien State Park office. Or bring your own. And, yes, William O’Brien State Park features trailer access to the St. Croix River. The boat ramp is located near Alice Lake and right one the canal to the river.

Does William O’Brien State Park have a campground?

Yes, William O’Brien State Park offers a huge campground for traditional tent and RV camping, as well as other campsites.

• 114 drive-in sites.
• 71 electric sites .
• 3 are wheelchair-accessible and near the restrooms .
• RV length limit is 60 feet.
• 4 rustic tent-only group camps; three sites accommodate up to 35. The Riverside Camp accommodates up to 50 people.
• 3 private and secluded walk-in campsites.
• 4 camper cabins; two are accessible; one camper cabin is available year-round.

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How big is William O’Brien State Park in Minnesota?

William O’Brien State Park started with only 180 acres. Today, visitors to William O’Brien State Park can enjoy 1,653 acres.

Is William O’Brien State Park buggy? Mosquitos? Ticks?

I noticed a few bugs here and there at William O’Brien State Park. But nothing too fierce. However, I always wear picaridin to ward off ticks and mosquitoes. And I love Aunt Fannie’s DEET-free mosquito wipes.

How long and how difficult are the hiking trails at William O’Brien State Park?

William O’Brien State Park features 16 miles of hiking trails. They range from easy to challenging. Some of the best trails at William O’Brien State Park in Minnesota include:

• The self-guided 1.5-mile interpretative Riverside Trail (easy)
• 3.8-mile one-way Prairie Overlook Trail (hilly / moderately challenging to challenging with two steep hills with loose gravel on one of them)
• 1 mile Beaver Lodge Trail takes you next to a beaver dam (easy mowed path)
• 1.5-mile loop Wedge Hill Savanna Trail (hilly / moderately challenging to challenging )

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Make sure your hiking plans include Beaver Lodge Trail to see the huge beaver lodge. And maybe a glimpse of the beavers at work.

Snowshoeing or cross-country skiing trails at William O’Brien State Park?

Yes. William O’Brien State Park offers five miles of ungroomed x-skiing trails and eight miles of snowmobile trails. Additionally, you can snowshoe anywhere in the park in the winter (except groomed trails).

Are hiking poles needed on the trails at William O’Brien State Park?

Yes. While you won’t need hiking poles on most trails, I recommend bringing them along. I wish I had brought mine along on the hilly Prairie Overlook Trail. This hiking trail doesn’t seem like much of a threat. However, lots of loose gravel made it difficult to descend. Hiking poles would have been helpful to have the extra leverage to balance and avoid sliding.

What are the best views at William O’Brien State Park?

William O’Brien State Park is so diverse with its landscape that you’ll find lots of scenic views. One of the best views is to check out the Beaver Lodge on Beaver Lodge Trail. I especially loved the scenic views along the St. Croix River. And the Prairie Overlook Trail provides some beautiful views at William O’Brien State Park.

And if you time it just right, you may see a passenger train pass above you on the scenic trestle. When you loop back around, take care crossing the railroad tracks. Look both ways!

Are there bike trails at William O’Brien State Park?

Yes, William O’Brien State Park offers a short two-mile paved bike trail.

Does William O’Brien State Park have horse trails?

No. William O’Brien State Park does not offer horse trails.

Does William O’Brien State Park have a visitor center? Modern restrooms?

William O’Brien State Park features a visitor center site and interpretive exhibit. Here you’ll learn more about beavers and how they help the wildlife. You’ll also get an overview of all the different scenic hiking trails and upcoming naturalist programs.

The visitor center offers modern flush restrooms all year. Additionally, you’ll find seasonal, modern restrooms in the campground, picnic area, as well as Alice Lake beach.

Is William O’Brien State Park dog-friendly?

Yes. Leashed dogs and pets are welcome at William O’Brien State Park. All Minnesota state parks welcome dogs except inside buildings, including the camper cabins (with the exception of service dogs). Leashes must be six feet or less.

Are there bears at William O’Brien State Park?

Bear sightings are not common at William O’Brien State Park.

Is firewood available at William O’Brien State Park?

Yes. You can purchase firewood at the park office when open. Or buy certified safe-to-move firewood from a gas station. Additionally, download the Yodel app to purchase firewood at Minnesota state parks. You can also purchase your vehicle permits from the Yodel app.

Why can’t you bring in your own firewood? To protect Minnesota trees, you can only burn certified wood on MN DNR land. Collection is not allowed in state parks and you may not bring firewood from home. This helps prevent spreading harmful insects and diseases.

How far is William O’Brien State Park from the Twin Cities – Minneapolis and St. Paul (MSP) airport?

William O’Brien State Park is located 43 miles from the Minneapolis – St. Paul (MSP) International Airport.

What’s nearby William O’Brien State Park? Top things to do near William O’Brien State Park?

William O’Brien State Park is located near quite a few fun things to do in Minnesota.

• Stop at the scenic and historic St. Croix Boom Site (pictured). Only 11 miles from William O’Brien State Park, this wayside is a designated National Historic Landmark. A boom is where a barrier is placed on a waterway to secure newly lumbered floating logs.
• Just 20 miles away is Taylor Falls, home of Interstate State Park. Here you’ll find glacial potholes, ancient lava flows, and scenic views overlooking the St. Croix River.
• If you’re planning to hike all 66 Minnesota state parks, then visit nearby Wild River State Park in Center City, MN.
• Even closer is one of Minnesota’s best roadside attractions. The quirky and poignant Fraconia Sculpture Park is near William O’Brien State Park – just 13 miles away.
• And you must stop at one of Minnesota’s prettiest river towns. Stillwater, Minnesota offers a lot of history, shopping, restaurants, a cool lift bridge, and more. I especially loved taking the stairway tour around Stillwater, MN.

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When was William O’Brien State Park in Minnesota established?

William O’Brien State Park was established in 1947.

How did William O’Brien State Park get its name?

William O’Brien State Park is named in the memory of a lumber baron with the same name. Alice Lake is named after his daughter.

Does William O’Brien State Park host deer hunts? Is William O’Brien State Park closed during deer season?

Yes. William O’Brien State Park typically hosts deer hunts during deer hunting season. During this time, the park usually closes to guests for a couple of days.

For a complete list of which Minnesota state parks are closed or limited to the public during deer season, see my post: Hiker safety: MN state parks that host deer hunts.

Hiking safety tip during deer season: Wear bright orange when hiking during deer season. I typically avoid hiking even when the state park is partially open to non-hunters.

A list of the best Minnesota state parks

All Minnesota state parks are the best in my opinion. You can read reviews of each one to create your own list of top-ranked Minnesota state parks: Take the Minnesota state park challenge

• Afton State Park | Hastings, MN (26 miles)
• Banning State Park | Sandstone, MN (97 miles)
• Bear Head Lake State Park | Ely, MN (240 miles)
• Beaver Creek Valley State Park | Caledonia, MN (148 miles)
• Big Stone Lake State Park | Ortonville, MN (186 miles)
• Blue Mounds State Park | Luverne, MN (208 miles)
• Buffalo River State Park | Glyndon, MN (240 miles)
• Camden State Park | Lynd, MN (161 miles)
• Carley State Park | Plainview, MN (88 miles)
• Cascade River State Park | Lutsen, MN (257 miles)
• Charles A. Lindbergh State Park | Little Falls, MN (112 miles)
• Crow Wing State Park | Brainerd, MN (134 miles)
• Father Hennepin State Park | Isle, MN (113 miles)
• Flandrau State Park | New Ulm, MN (93 miles)
• Forestville / Mystery Cave State Park | Preston, MN (115 miles)
• Fort Ridgely State Park | Fairfax, MN (99 miles)
• Fort Snelling State Park | Bloomington / St. Paul, MN (2 miles)
• Franz Jevne State Park | Birchdale, MN (336 miles)
• Frontenac State Park | Frontenac, MN (62 miles)
• George H. Crosby Manitou State Park | Finland, MN (231 miles)
• Glacial Lakes State Park | Starbuck, MN (156 miles)
• Glendalough State Park | Battle Lake, MN (194 miles)
• Gooseberry Falls State Park | Two Harbors, MN (197 miles)
• Grand Portage State Park | Grand Portage, MN (308 miles)
• Great River Bluffs State Park | Winona, MN (136 miles)
• Hayes Lake State Park | Roseau, MN (343 miles)
• Hill Annex Mine State Park | Calumet, MN (197 miles) Editorial Note: This park is now closed as mining has resumed.
• Interstate State Park / Taylors Falls State Park | Taylors Falls, MN (56 miles)
• Itasca State Park | Park Rapids, MN (219 miles)
• Jay Cooke State Park | Carlton, MN (146 miles)
• John A. Latsch State Park | Winona, MN (99 miles)
• Judge C.R. Magney State Park | Grand Marais, MN (282 miles)
• Kilen Woods State Park | Lakefield, MN (153 miles)
• Lac qui Parle State Park | Watson, MN (141 miles)
• Lake Bemidji State Park | Bemidji, MN (230 miles)
• Lake Bronson State Park | Karlstad, MN (409 miles)
• Lake Carlos State Park | Alexandria, MN (152 miles)
• Lake Louise State Park | Le Roy, MN (113 miles)
• Lake Maria State Park | Monticello, MN (60 miles)
• Lake Shetek State Park | Currie, MN (168 miles)
• Lake Vermilion-Soudan Underground Mine State Park | Soudan, MN (229 miles)
• McCarthy Beach State Park | Side Lake, MN (227 miles)
• Maplewood State Park | Pelican Rapids, MN (217 miles)
• Mille Lacs Kathio State Park | Onamia, MN (108 miles)
• Minneopa State Park | Mankato, MN (82 miles)
• Monson Lake State Park | Sunburg, MN (141 miles)
• Moose Lake State Park | Moose Lake, MN (116 miles)
• Myre-Big Island State Park | Albert Lea, MN (93 miles)
• Nerstrand Big Woods State Park | Nerstrand, MN (52 miles)
• Old Mill State Park | Argyle, MN (350 miles)
• Rice Lake State Park | Owatonna, MN (70 miles)
• St. Croix State Park | Hinckley, MN (105 miles)
• Sakatah Lake State Park | Waterville, MN (60 miles)
• Savanna Portage State Park | Northeast Aitkin, MN (149 miles)
• Scenic State Park | Bigfork, MN (232 miles)
• Schoolcraft State Park | Deer River, MN (198 miles)
• Sibley State Park | New London, MN (128 miles)
• Split Rock Creek State Park | Jasper, MN (202 miles)
• Split Rock Lighthouse State Park | Two Harbors, MN (204 miles)
• Temperance River State Park | Schroeder, MN (239 miles)
• Tettegouche State Park | Silver Bay, MN (217 miles)
• Upper Sioux Agency State Park | Granite Falls, MN (122 miles) – Note: Minnesota returned this park’s land to the Native Americans in February 2024. It is no longer open to the public.
• Whitewater State Park | Altura, MN (99 miles)
• Wild River State Park | Center City, MN (58 miles)
• William O’Brien State Park | Scandia / Marine on the St. Croix, MN (43 miles)
• Zippel Bay State Park | Williams, MN (345 miles)

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Pin it for later: A local’s guide to William O’Brien State Park in Minnesota

Please share and pin this guide for when you visit William O’Brien State Park in Marine of St. Croix, MN – one of the best historic Minnesota state parks.

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