William O'Brien State Park

About this park

William O'Brien State Park traces its creation to a single act of family generosity: in 1945, twenty years after lumberman William O'Brien's death, his daughter Alice O'Brien donated 180 acres of St. Croix riverfront land to the state in his memory. The gift arrived at a pivotal moment, since Minnesota did not yet have a state park anywhere near the rapidly growing Twin Cities, and the legislature eagerly accepted the donation, formally ratifying the park two years later in 1947. Located roughly two miles north of the historic village of Marine on St. Croix, the 1,520-acre park sits along a stretch of the St. Croix River valley that was home to Dakota and Ojibwe communities for generations before European settlement, and the timber wealth that built William O'Brien's fortune came directly from the same pine forests that once blanketed this valley before large-scale logging cleared them. That family connection to the lumber industry gives the park's very existence a certain historical irony, transforming land once valued for its timber into permanently protected public parkland. Thanks largely to its proximity to the Twin Cities, William O'Brien consistently ranks among the top five most-visited state parks in Minnesota, drawing a steady stream of day-trippers and campers for fishing northern pike, walleye, bass, and trout along the St. Croix riverbank, alongside hiking, canoeing, and cross-country skiing. That combination of easy metro-area access and genuine riverside scenery has made the park a reliable weekend destination for generations of Twin Cities families since its 1947 founding.