🌤 Weather at Three Mile Lake State Park by season
| Spring | Summer | Fall | Winter |
|---|---|---|---|
| 26–70 °F | 60–83 °F | 27–75 °F | 10–32 °F |
Each range runs from the coldest monthly average low to the warmest monthly average high in that season (1991-2020 climate normals), measured at Colo, 11 mi away, elevation 1,000 ft. Conditions at the park can differ from the station, especially where elevation differs — check a forecast before you go.
🏆 Iowa’s Prairie Lake Getaway — Peaceful Camping, Fishing & Nature on Rolling Grasslands — Updated for 2026 with camping reservations, fishing info, trails, and seasonal guide
Iowa doesn’t do dramatic. It does peaceful. And at Three Mile Lake State Park, peaceful is perfection — a 730-acre prairie lake ringed by grasslands and oak-hickory timber, where the loudest sound is a red-winged blackbird calling from the cattails and the biggest decision of the day is whether to fish from the pier or the canoe. Located in Union County in southern Iowa, Three Mile Lake is the kind of state park that locals treasure and tourists haven’t found yet.
The lake was built in 1983 for recreation and flood control, and today the park offers modern camping, excellent channel catfish and largemouth bass fishing, a swim beach, hiking trails through tallgrass prairie, and the kind of quiet that only the rural Midwest can deliver. If you’re looking for a lake without crowds, a campsite without reservations eight months in advance, and a fishing hole where the catfish cooperate — this is your park.
What Makes Three Mile Lake Charming
Prairie Fishing
730-acre lake with excellent channel catfish, largemouth bass, bluegill, and crappie. Fishing pier and boat ramp.
Modern Camping
Modern campsites with electric hookups near the lake. Rarely crowded — Iowa’s best-kept camping secret.
Tallgrass Prairie
Hiking trails through native tallgrass prairie and oak-hickory timber — Iowa’s original landscape.
Swim Beach
Sandy swim beach for hot summer days — a refreshing prairie lake dip.
Activities
- 🎣 Fishing: Channel catfish, largemouth bass, bluegill, crappie. Fishing pier, cleaned shoreline access, boat ramp
- 🏊 Swimming: Designated swim beach with sandy shore
- 🚤 Boating: Boat ramp for small watercraft. Electric motors and gas motors permitted
- 🚶 Hiking: Multi-use trails through tallgrass prairie and timber. Wildflowers in spring/summer
- 🐦 Birding: Prairie habitat attracts grassland birds — dickcissel, meadowlark, bobolink, red-winged blackbird
- 🦌 Wildlife: White-tailed deer, wild turkeys, and an occasional bald eagle
When to Visit: Seasonal Guide
| Season | Months | Weather | Best For |
|---|---|---|---|
| ☀️ Summer | Jun–Aug | 80-90°F | 🏆 Swimming, full lake recreation, warm camping. Tallgrass prairie in bloom |
| 🍂 Fall | Sep–Nov | 50-70°F | Fishing continues. Fall color in timber. Quiet camping. Hunting season |
| 🌸 Spring | Apr–May | 50-70°F | Wildflowers in prairie. Crappie spawning. Bird migration |
| ❄️ Winter | Dec–Feb | 15-35°F | Ice fishing for crappie and bluegill. Deer and turkey hunting |
Camping
| Feature | Details |
|---|---|
| ⛺ Sites | Modern campsites with 50-amp electric hookups |
| 🚿 Amenities | Modern restrooms, showers, dump station |
| 🏕️ Non-Electric | Basic sites also available at lower cost |
| 📅 Reservations | Iowa DNR reservation system. Many sites first-come, first-served |
Budget Calculator
| Expense | Day Trip | Camping Weekend | Notes |
|---|---|---|---|
| Park Entry | FREE | FREE | Iowa state parks are free to enter |
| Camping (2 nights) | — | $16-26/night | Non-electric to electric sites. Very affordable |
| Fishing License | $8-48 | $8-48 | Iowa fishing license required |
| Total (2 adults) | FREE-$48 | $40-$100 | One of the most affordable parks in America |
Frequently Asked Questions
Is it crowded?
No — Three Mile Lake is one of Iowa’s least crowded state parks. Even summer weekends rarely fill up. It’s a genuine hidden gem.
What fish are in the lake?
Channel catfish are the star — excellent numbers and size. Also largemouth bass, bluegill, crappie, and some walleye.
Can I boat?
Yes — there’s a public boat ramp. Gas motors and electric motors both permitted on the 730-acre lake.
What’s the prairie like?
Native tallgrass prairie — Iowa’s original ecosystem. In summer, grasses reach 6+ feet with wildflowers. Trails wind through it alongside oak-hickory timber.
How do I get there?
Southern Iowa, Union County — about 3 miles east of Afton, IA on Highway 34. About 75 miles south of Des Moines.
🌾 Iowa’s Quietest Lake Secret
Some parks shout. Three Mile Lake whispers. It whispers through tallgrass prairie that sways in the wind like a green ocean. Through mornings so quiet you can hear a bobber hit the water from across the lake. Through sunsets that paint the entire western sky while you sit by your campfire and think about exactly nothing. This is Iowa at its most honest — a prairie lake, a fishing pole, a campsite under the oaks, and the kind of peace that makes you wonder why you spent all that money on the fancy vacation. Three Mile Lake doesn’t have a single thing to prove. That’s why it’s perfect.
📍 Address: Three Mile Lake State Park, Afton, IA 50830
📞 Phone: (641) 347-5798
Explore More Iowa State Parks
Three Mile Lake State Park is one of many outstanding state parks in Iowa. Discover more parks in our Best State Parks in Iowa guide, or use our Park Finder to search by activity, location, or features.
More parks in Iowa: Dinesen Prairie State Preserve and Rock Creek State Park. See the full Iowa state parks guide.
⛺ Camping at Three Mile Lake State Park: Campgrounds & Cabins
| Campsites | Two campgrounds with electrical hookups (20/30/50 amp on electric sites); the county tourism page states 80 total sites, while the county's own facility listing states 100 total sites with the South Campground alone holding 48. Electric sites $20/night, non-electric/tent $15/night. Picnic sites, a fish cleaning station and a dump station serve the campgrounds; a year-round heated shower house has flush toilets and sinks. |
|---|---|
| Cabins & Lodging | 9 log camping cabins, sleep 6, $65/night Sunday-Thursday and $75/night Friday/Saturday; the Lakeshore Cabin is $80/night Sunday-Thursday and $90/night Friday/Saturday. |
| Pets | Pets must be controlled at all times and may not be tied to trees or other county property. |
| Reservations | Campsites are not reservable; first-come, first-served, self-registration by envelope at the entrance. Cabins and shelter houses can be reserved online up to 12 months in advance at mycountyparks.com, or call the Union County Conservation office at (641) 347-5100. |
| Special sites | 1 lodge and 4 shelter houses available to rent. Dump station and wireless internet at the campground. Three Mile Lake is a Union County recreation area, not an Iowa DNR state park. |
| Season notes | Campground and shower house open year-round. |
Camping questions about Three Mile Lake State Park
Can you camp at Three Mile Lake State Park?
Two campgrounds with electrical hookups (20/30/50 amp on electric sites); the county tourism page states 80 total sites, while the county's own facility listing states 100 total sites with the South Campground alone holding 48. Electric sites $20/night, non-electric/tent $15/night. Picnic sites, a fish cleaning station and a dump station serve the campgrounds; a year-round heated shower house has flush toilets and sinks.
How do you reserve a campsite at Three Mile Lake State Park?
Campsites are not reservable; first-come, first-served, self-registration by envelope at the entrance. Cabins and shelter houses can be reserved online up to 12 months in advance at mycountyparks.com, or call the Union County Conservation office at (641) 347-5100.
Are there cabins at Three Mile Lake State Park?
9 log camping cabins, sleep 6, $65/night Sunday-Thursday and $75/night Friday/Saturday; the Lakeshore Cabin is $80/night Sunday-Thursday and $90/night Friday/Saturday.
Are pets allowed at the Three Mile Lake State Park campground?
Pets must be controlled at all times and may not be tied to trees or other county property.
Source: unioncountyiowatourism.com (verified July 2026). Details change seasonally — confirm when booking.
🐾 Dogs & Pets at Three Mile Lake State Park
- Pets allowed? statewide rule
- Pets are allowed in Iowa state parks and recreation areas, including trails and campgrounds, but must be kept on a leash of six feet or less or confined.
- Leash rule statewide rule
- Leash or chain not to exceed 6 feet, led or carried by the owner, or confined
- Beaches & swim areas statewide rule
- Animals are prohibited within designated beach areas statewide
- Cabins & lodging statewide rule
- Only dogs or assistive animals are allowed in designated dog-friendly cabins/yurts (limit two dogs); all other cabins are pet-free; dogs must be kenneled if left unattended inside
- Statewide exceptions statewide rule
- Hunting dogs in designated hunting areas during season are exempt from the leash rule; pets may not be left unattended in campgrounds
Are dogs allowed at Three Mile Lake State Park?
Pets are allowed in Iowa state parks and recreation areas, including trails and campgrounds, but must be kept on a leash of six feet or less or confined. Individual parks can post stricter rules — check signage on arrival.
Rules verified July 2026 via iowadnr.gov. More: Iowa state parks guide · Dog rules in all 50 states compared
Park Location
Plan your gear for Three Mile Lake State Park
From our editorial guides, matched to this park’s activities:
