William O'Brien State Park
Overview
This area has drawn people for centuries, including: Dakota and Ojibwe tribes utilizing local resources; European trappers drawn by the fur-trade industry; and lumberjacks seeking to harvest the “endless stands” of white pine. The era of timber harvesting began in 1839 and flourished until lumber companies had cleared the St. Croix River valley of pines. Local lumber baron William O’Brien bought much of the land owned by the lumber companies. In 1945, his daughter, Alice O’Brien, donated 180 acres to be developed as a state park in his memory. The park now protects 1,880 acres of prairie, oak savanna, river floodplain and hardwood forest.
- Trails
- 10
- Viewpoints
- 10
- Activities
- 0
- POIs
- 32
Opening Hours
08:00 AM – 10:00 PM
Emergency SOS
Amenities Available
- Paved Parking Lots
Designated vehicle parking areas with clearly marked spaces and ADA-accessible spots mandated by federal law. Most parks offer free or low-cost daily parking passes.
- Restrooms / Flush Toilets
Modern restroom facilities with running water and proper sanitation. Subject to seasonal closures in northern states during winter months.
- Drinking Water Fountains
Potable water stations distributed throughout the park, tested regularly for safety to ensure clean water access for all visitors.
- Picnic Areas & Shelters
Covered pavilions equipped with tables and built-in grills. Shelters are often reservable for group events and birthday parties.
- Visitor / Ranger Station
Information hub staffed by rangers or volunteers offering maps, wildlife briefings, and educational programs for school groups and families.
- Hiking & Nature Trails
Marked paths ranging from easy, paved walks to rugged backcountry routes, blazed with color-coded markers and difficulty ratings.
- Campgrounds
Tent and RV sites featuring fire rings and picnic tables. Some include full electric hookups, reservable through Recreation.gov.
- Sports Courts
Basketball, tennis, volleyball, and pickleball courts available in most parks, with lighting for evening play in urban locations.
- Swimming Areas / Beaches
Designated swim zones with seasonal lifeguard coverage. Daily water quality reports are posted at the entrance and online.
- Fishing Piers & Access
Accessible fishing spots and ADA-compliant piers along rivers and lakes. A valid state fishing license is required to fish.
- RV Sanitation Station
- Amphitheatre
0.9 mi from park centre
Open · 08:00 – 22:00
- Paved Parking Lots
- Restrooms / Flush Toilets
- Drinking Water Fountains
- Picnic Areas & Shelters
- Visitor / Ranger Station
- Hiking & Nature Trails
- Campgrounds
- Swimming Areas / Beaches
Required Permits
VEHICLE PERMITSRequired
Permits required; purchase at park office or entrance kiosk, or online at mndnr.gov/permit.
Alerts & Advisories
Stay informed before heading out
Safety Tips
Safety Advisory
- William O'Brien State Park currently has significant closures and recreation alerts due to major construction projects.
- The Lake Alice recreation area is closed to all public activities, including swimming and fishing, as the Minnesota Department of Natural Resources executes a $325,000 reconstruction project.
Popular/Nearby Trails
Hiking (Beaver Lodge Trail)
Hiking (Wedge Hill Savanna Trail)
Hiking (Woodland Edge Trail)
Hiking (Prairie Overlook Trail)
Hiking (Rolling Hills Savanna Trail)
Hiking (Riverside Trail)
Hiking (Wetland Trail)
Hiking (Hardwood Hills Trail)
Hiking (Southern Trails)
Paved
Nearby Viewpoints
Primitive Group Camp
Campsite
0.5 mi
Walk-In Campsite
Camping
0.5 mi
Campground
0.6 mi
Visitor Center
Family Restroom
0.7 mi
Athletic Fiels
Sporting
0.9 mi
Rentals (Canoe, Kayak)
Rentals
0.9 mi
Picnic Area
0.9 mi
Amphitheater
1.0 mi
Campground
1.0 mi
Primitive Group Camp
Campsite
1.1 mi
Nearby Points of Interest
Reviews & Ratings
Community Photos
Frequently Asked Questions
What are the opening hours of William O'Brien State Park?
William O'Brien State Park is open every day from 8:00 AM to 10:00 PM.
What is William O'Brien State Park?
This area has drawn people for centuries, including: Dakota and Ojibwe tribes utilizing local resources; European trappers drawn by the fur-trade industry; and lumberjacks seeking to harvest the “endless stands” of white pine.
Where is William O'Brien State Park located?
William O'Brien State Park is located in Marine on St. Croix, Minnesota, United States.
How many trails are there at William O'Brien State Park?
William O'Brien State Park has 10 mapped trails covering 18.1 miles in total. The longest is Hiking (Woodland Edge Trail) at 3.4 miles.
What is there to see at William O'Brien State Park?
Places to see at William O'Brien State Park include Athletic Fiels, Rentals (Canoe, Kayak), Camper Cabin, Park Entrance and Trailer Access.
What facilities are available at William O'Brien State Park?
Facilities at William O'Brien State Park include Amphitheatre, Campgrounds, Drinking Water Fountains, Fishing Piers & Access, Hiking & Nature Trails, Paved Parking Lots, Picnic Areas & Shelters, Restrooms / Flush Toilets and 4 more.
Is there parking at William O'Brien State Park?
Yes, William O'Brien State Park has parking (Paved Parking Lots).
Can I camp at William O'Brien State Park?
Yes, William O'Brien State Park has 5 campsites marked on its map, including Primitive Group Camp and Walk-In Campsite.
How can I contact William O'Brien State Park?
You can contact William O'Brien State Park by phone at 8886466367.
What safety tips should visitors to William O'Brien State Park know?
William O'Brien State Park currently has significant closures and recreation alerts due to major construction projects. The Lake Alice recreation area is closed to all public activities, including swimming and fishing, as the Minnesota Department of Natural Resources executes a $325,000 reconstruction project. This long-term project aims to dredge the area and replace a failed 1960s-era water control structure that previously drained the lake, with restrictions expected to last until fall 2027.
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