About The Park
Welcome to Willow Mill Campsite
Willow Mill Campsite has been a fixture in Rio, Wisconsin since 1968 — a family-run campground on the water in the heart of Columbia County. We sit along County Highway SS, tucked between Madison and Wisconsin Dells, with lakefront sites, mature shade trees, and a community of campers who come back season after season. Rio calls itself Camper Country USA, and Willow Mill has been part of that reputation for a long time. We’re glad you’re here.
Explore the Area Around the Park
Our location here in Rio puts you in a strong spot whether you’re here for work or here for play. Columbia County sits at a crossroads between some of the best the state has to offer. To the south, Madison is a full city with a small city feel — great restaurants, live music, farmers markets, and plenty of walkable neighborhoods. Epic Systems in Verona and the University of Wisconsin are both major employers in the region, making Rio a practical home base for contract workers and traveling professionals. Head north and Wisconsin Dells delivers a completely different energy with water parks, boat tours, mini golf, go-karts, and so much more. Closer to home, the Wisconsin River corridor, Devils Lake State Park, and the rolling farmland of Columbia County give easy access you plenty of outdoor space without having to drive too far. Head to our nearby attractions page to see more.
Long Term Stays Welcome
Willow Mill has been a seasonal home for campers since 1968, and that history shows in the way the community here operates. Long term guests get the same large, shaded sites with full hookups, picnic tables, and fire rings plus access to everything on the property, from the pool and kayak rentals to the game room, pavilion, and clubhouse. Our camp store is stocked with RV supplies and everyday essentials so you’re not making constant runs into town, and practical amenities like laundry facilities, private bathrooms, a dump station, and propane refills keep your extended stay comfortable. We’re pet friendly with a dog park on the property and we have a gated entry for extra security. If you’re looking for a seasonal spot in Columbia County, we’d love to have you. Head to our long term RV page to learn more.
Park Information
Your four-legged family members are welcome to enjoy the lake life too.
Our office is open Mon-Thurs from
10 AM-7 PM and Fri-Sun from 8 AM-8 PM.
