Willow River State Park in Hudson, Wisconsin Post author: Post published: Post category:Hike / Hudson / North America / USA / Wisconsin Waterfalls, caves, and frogs for these little explorers. A great day outdoors at Willow River State Park in Wisconsin! You Might Also Like Independence Rock, Wyoming Minnesota’s North Shore: Split Rock Lighthouse & Pebble Beach Minnesota’s Como Zoo & Conservatory: Winter Flower Show