William O'Brien State Park is a 1520acre state park of Minnesota, USA, along the St. Croix River. Its hiking trails traverse rolling glacial moraine, riparian zones, restored oak savanna, wooded areas and bogs. It is a popular place for birdwatching, picnics, camping, cross-country skiing, canoeing, fishing, and other typical outdoor recreational activities.The park is located approximately two miles north of the town of Marine on St. Croix, Minnesota.HistoryThe St. Croix river valley was inhabited by Dakota and Ojibwa. European trappers commercialized the fur-trade in the 17th century. Extensive logging took place in the mid-19th century; white pines were the target and most other tree species were ignored. Once the white pine was gone the lumber companies were happy to sell, and a lumber baron named William O'Brien bought up much of the land for his personal estate. In 1945, 20 years after William O'Brien's death, his daughter Alice offered 180acre along the riverfront to the state. The donation was eagerly accepted, as Minnesota did not yet have a state park near the Twin Cities, and the park was ratified by the legislature two years later. The proximity to the metro area was a mixed blessing. Land was added to the park at every opportunity, to reduce crowding and to prevent housing developments from being built right up to the boundary. In 1958‚ S. David Greenberg donated Greenberg Island in memory of his parents. Accessible only by canoe‚ the island has become a haven for wildlife and wildflowers. The park was expanded into the bluffs west of Highway 95 and a second campground added. A large tract was added in 1973, leapfrogging a rail line, and another 120acre came in 1986. William O'Brien remains one of the top five most-visited state parks in Minnesota.Before you head to Marine on Saint Croix, plan trip itinerary details with our user-friendly Marine on Saint Croix tour planner, to make sure you see all that Marine on Saint Croix has to offer, including William O'Brien State Park.
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We are so fortunate to have our state park system. Inviting, typically well kept, and so many recreational opportunities. O'Brien lives up to that, too. Great hiking trails even in the spring they are... more »
Ended up here after trying to go to Interstate but it was too icy; great views of the river and a wonderful park for hikes! more »
There are two campsites available, (also group sites) with showers and flush toilets, some sites have electric plug ins. The Riverside camp is by the St. Croix river, with a wooded trail along the riv... more »
Dora Ragin Powell
This was one of my better camping experiences. We had one of the sites around the loop, not in the center, so we had quite a bit of space and woods for the kids to roam in. You could hear cars at night on the road right by the campground, which is really my only complaint. Otherwise, this is a very special and beautiful place that our whole family loved. The trails by the river were gorgeous and it wasn't too crowded even though the whole site was booked. We will definitely be going back.
Beautiful tucked away state park. Nice walking trails, lots of grills and picnic tables, clean secluded camp sites, small swimming area, boat launch & lots of public parking. The swim are and boat launch is pretty far from the savanna campgrounds, but this is a great place to check out. Just north of lovely Still Water.
Wonderful weather camping along the lower camp ground closer to the river, Riverway. The camp spots were nice and the fire felt good even in summer. It was fun to wake up in the morning and see the fog along the river and walk along the trail. I got firewood at the park office for 6$. You need at least 2 or 3 bundles, they burn fast.
Beautiful Minnesota State Park on the St. Croix River. Fantastic wildlife to observe and photograph. Canoe, kayak, and paddle board rentals. Many picnic areas with 2 large, covered picnic areas that can be reserved for large gatherings. Great campgrounds both by the river and in the upper park; and camper cabins too! Lake Alice has a swimming beach and a fishing pier. The park will loan you fishing poles of you want to try it out! Beautiful wildflowers and frequently nesting Sandhill Cranes in the spring, breathtaking colors in the fall, and cross country skiing in the winter!
We went to see the fall colors. It was amazing!
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