William O'Brien State Park

Name: The Journey of a Water Droplet- Children's Program
Start: 2026-11-21T10:00:00-06:00
Location: William O'Brien State Park

Minnesota State Park

⚠️ Season Close October 19th, 2026

The dump station, shower facilities, flushable toilets and jug fillers will be available through Sunday, October 18th.

Show all 2 notices

Beginning October 19th, seasonal closures will begin including: Dump station Shower and restroom facilities in the campgrounds Jug fillers throughout the campgrounds and Day Use Area Flushable toilets in the Day Use Area Riverway Campground, Wedge Hill and Riverside Group Camps, walk-in sites, and some loops in the Savanna Campground Vault toilets will be available in the Day Use Area and Savanna Campground. Camper or RV tanks can be filled with potable water behind the Ranger Station. Flushable toilets will be available at the Visitor Center during park hours.
The public water access on the St. Croix is currently closed due to low water levels and high sediment. Small, non-motorized watercraft are still able to launch in the current conditions. Motorized watercraft should use alternate launches, such as Osceola or Somerset landing.

Lake Alice reconstruction project
In early August 2025, a mechanical failure of Lake Alice's water control structure resulted in a drawdown of the lake. After evaluating options for the site, DNR staff has a plan to replace the lake's water control structure and dredge the park's public water access.
The following areas are closed to the public through construction completion (estimated fall 2027): Lake Alice beach, Lake Alice fishing pier and accessible canoe/kayak launch on Lake Alice.
For construction updates, visit the Lake Alice construction page.
Updated September 22nd, 2026

HoursDaily from 8 a.m. until 10 p.m.

Entrance fee$7 / vehicle

CampingYes

RV hookupsPrimitive only

Cabins / lodgeYes

Book a campsite Directions Official Minnesota DNR page Park map Log a visit Campground map Winter map

William O'Brien State Park entrance fee

$7 per vehicle — One-day vehicle permit $7; year-round permit $35 ($26 for an additional vehicle, $30 motorcycle, $12 with a disability permit). Free year-round permits for disabled veterans, active-duty military and members of Minnesota’s 11 federally recognized tribes.

William O'Brien State Park hours

Daily from 8 a.m. until 10 p.m.

Hours as published by Minnesota DNR. Check the official page before a long drive.

About William O'Brien State Park

Rolling wooded hills over the St. Croix, an hour out of the Twin Cities, with northern, walleye, bass and trout in the channels. Paddle one of the finest canoeing rivers anywhere, ski it in winter, and catch a naturalist program most of the year.

Things to do

🥾 Hiking
🚲 Biking
🛶 Paddling
🏊 Swimming
🎣 Fishing
⛵ Boating
🐦 Birding

Amenities & facilities

🏕️ Campsites
🚿 Showers
🚻 Restrooms
🛖 Cabins
👥 Group Sites
🚤 Boat Ramp
🚐 RV Dump Station
🌿 Nature Center
♿ Accessible Facilities

RV / campsite hookups

⛺ Primitive / No Hookups

Camping options

Drive-in Sites
Electric Sites
Accessible Sites (Three acessible campsites)
Group Camp

Lodging options

Camper Cabins · Reserve

Contact

Phone651-539-4980

Address16821 O'Brien Trail North, Marine on St. Croix, MN 55047

Upcoming events at William O'Brien State Park

The Journey of a Water Droplet- Children's ProgramNov 21, 2026 · 10:00 AM
Rare, Common, or Invasive Nature TableNov 21, 2026 · 12:30 PM
Backyard Birding (all ages)Nov 28, 2026 · 10:00 AM
Friendly Giants- Pine Tree Children's ProgramNov 28, 2026 · 1:00 PM

Event details and registration are on the Minnesota DNR calendar.

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