William O'Brien State Park

16821 O'Brien Trail North
Marine on Saint Croix, MN 55047


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.

Park Highlights:
Canoeing on the St. Croix
Cross-country Skiing
Naturalist Programs
Bird Watching
Oak Savanna Restoration


Drive-in Sites 114 Sites
Some are located in shaded areas, other are in open areas.

Electric Sites 71 Sites
Located in both campgrounds.

RV Length Limit 60 Feet
Length is measured from front of tow vehicle to rear of vehicle being towed.

Wheelchair Accessible Sites 3 Sites
Located near the restrooms.

Group Camp 4 Sites
Sites are rustic with running water and vault toilets.
Riverside Camp - accommodates up to 50 people. Tents only.
Site 1, 2, and 3 - accommodates up to 35 people. Tents only.



Wheelchair Accessible Riverside Trail - 1.5 miles
The Riverside Trail is a fully accessible 1.5 mile loop that begins at the picnic grounds. It is self-guided with interpretive signs located along the trail. There are rest areas along the trail at approximately every 900 feet, and some of the rest areas have benches.

Self Guided Riverside Trail - 1.5 miles
Trail is accessible. Trail begins at picnic grounds.

Hiking 12 Miles
Trails range from easy to difficult. Trails wind through wooded areas, wetlands, and restored oak savanna areas.

Paved Bike 1.5 Miles


Cross Country Skiing 12 Miles
Trails are groomed for classic cross-country skiing and skate skiing. Trails range from easy to difficult.

Skate-Skiing 12 Miles
Snowshoe On Riverside Trail Only
Snowshoers are allowed only on the Riverside Trail. No snowshoeing is allowed west of the Visitor Center.

Recreation Facilities


Picnic Area 1 Picnic Area
Wheelchair accessible

Picnic Shelter Open Shelters
2 open shelters in the main picnic area and 1 behind the beach area on Lake Alice. All shelters have electricity. Large open shelter in picnic area contains a fireplace and is wheelchair accessible. Shelters can be rented by calling the park.

Volleyball 2 Locations
One volleyball area is near the swimming beach. The other volleyball area is near the ball field. Pick up equipment at park office.

Horseshoes 4 Horseshoe Pits
Located near the swimming beach and ball field. Pick up equipment at park office.

Golf Course Within 10 miles
Many near park.

Other Ballfield
Field has a backstop.


Warming House Visitor Center


Fishing Pier Wheelchair accessible
Fishing tackle is available on loan from the park office.

Swimming Beach Within the park
Beach located on Lake Alice. No lifeguard on duty.

Boat Access Boat Launch
Boat launch available on the St. Croix River.

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