Winneshiek County is a county in Iowa, United States, set in the Driftless Area of the northeast corner of the state, about 15 miles south of the Minnesota border. It had a population of 20,070 at the 2020 census and covers 690 square miles (1,800 km2) of mostly unglaciated bluff-and-valley terrain, centred near 43°17′N 91°52′W.
Decorah is the county seat, and its postal code is 52101. The county has 8 incorporated cities and towns, 20 civil townships, and a handful of unincorporated crossroads communities. It sits in the Central time zone and carries FIPS code 19191.
Towns & Villages in Winneshiek County
Decorah anchors the county both by population and by services; the rest of Winneshiek County is small incorporated towns spread through the valleys, plus unincorporated hamlets that never grew past a church, a store, or a grain elevator.
| Place | Type | Township | Pop. | ZIP |
|---|---|---|---|---|
| Decorah | City · seat | Decorah | 7,587 | 52101 |
| Calmar | City | Calmar | — | — |
| Castalia | City | Military | — | — |
| Fort Atkinson | City | Fremont | — | — |
| Jackson Junction | City | Jackson | — | — |
| Ossian | City | Pleasant | — | — |
| Ridgeway | City | Frankville | — | — |
| Spillville | City | Jackson | — | — |
| Bluffton | Unincorp. | Bluffton | — | — |
| Festina | Unincorp. | Frankville | — | — |
| Frankville | Unincorp. | Frankville | — | — |
| Freeport | Unincorp. | Decorah | — | — |
| Highlandville | Unincorp. | Highland | — | — |
| Hesper | Unincorp. | Hesper | — | — |
| Kendallville | Unincorp. | Burr Oak | — | — |
| Burr Oak | Unincorp. | Burr Oak | — | — |
Population figures are not published at this level of granularity by the Census Bureau for most of these places; only Decorah is a standalone census designation. The old page’s unattributed pop counts for the small unincorporated communities have been dropped rather than repeated as fact.
Townships
Iowa organizes its rural land into civil townships, and Winneshiek County has 20 of them — a dense grid even by Iowa standards, reflecting the county’s Driftless-Area terrain of narrow valleys that kept early settlement scattered.
| Township | Pop. (2020) | Main settlements |
|---|---|---|
| Decorah | — | Decorah, Freeport |
| Calmar | — | Calmar |
| Military | — | Castalia |
| Fremont | — | Fort Atkinson |
| Jackson | — | Jackson Junction, Spillville |
| Pleasant | — | Ossian |
| Frankville | — | Ridgeway, Frankville, Festina |
| Bluffton | — | Bluffton |
| Highland | — | Highlandville |
| Hesper | — | Hesper |
| Burr Oak | — | Burr Oak, Kendallville |
| Bloomfield | — | rural |
| Canoe | — | rural |
| Glenwood | — | rural |
| Lincoln | — | rural |
| Madison | — | rural |
| Orleans | — | rural |
| Springfield | — | rural |
| Sumner | — | rural |
| Washington | — | rural (Washington Prairie) |
ZIP Codes
- 52101 — Decorah (also serves the surrounding rural townships)
ZIP codes for the county’s other incorporated towns — Calmar, Castalia, Fort Atkinson, Jackson Junction, Ossian, Ridgeway, and Spillville — are not confirmed here and have been left off rather than guessed; most route mail through their own local post offices.
Geography
Winneshiek County sits in Iowa’s Driftless Area, the region of the Upper Midwest that the last continental glaciation skipped, leaving steep limestone bluffs, spring-fed trout streams, and narrow river valleys instead of the flat till plains found across most of the state. The Upper Iowa River cuts through the county roughly west to east, and its tributary valleys shape where the towns sit. Almost all of the county’s 690 square miles is land, with only a sliver of water.
The county borders seven others across two states:
- Fillmore County, Minnesota — northwest
- Houston County, Minnesota — northeast
- Allamakee County, Iowa — east
- Clayton County, Iowa — southeast
- Fayette County, Iowa — south
- Chickasaw County, Iowa — southwest
- Howard County, Iowa — west
See also: Allamakee County, Fayette County, Howard County.
Demographics
Winneshiek County had a population of 20,070 at the 2020 census, roughly holding steady from the previous decade before edging down since; the 2025 estimate puts it near 19,733. Decorah, home to Luther College, is the largest community with 7,587 residents; Calmar is the second-largest incorporated town. The county’s median household income runs close to the Iowa state figure of $71,433 (2023 ACS), typical for a small-college, farm-service county. Population density is about 29 people per square mile, well below the state average, a direct result of the Driftless Area’s rugged terrain limiting large-scale row-crop farming compared with counties on Iowa’s till plains.
Economy & Local Life
Agriculture remains the base of the county’s economy — dairy, corn, and soybeans on the flatter ridge tops, with the steep valley land often kept in pasture or timber. Decorah’s economy is anchored by Luther College, Vesterheim (the National Norwegian-American Museum), and Toyota Financial Savings Bank’s regional operations, plus a cluster of manufacturers and clinics that serve the wider county. The Nordic Fest, held every July in Decorah, is the county’s signature annual event, drawing visitors to celebrate the area’s heavy Norwegian settlement heritage with folk dancing, craft demonstrations, and a parade.
History
Winneshiek County was organized in 1847 and named for Chief Winneshiek of the Ho-Chunk (Winnebago) people, who were relocated to a reservation that once covered part of this area under an 1840s federal treaty. Early settlement concentrated around what became Fort Atkinson and Bloomfield townships in the late 1840s. Fort Atkinson itself grew up around a U.S. Army post built in 1840 to keep peace between the Ho-Chunk and neighboring Sac and Fox nations; the fort’s stone blockhouse still stands and is now a state preserve. Norwegian and Czech immigrants settled heavily through the mid-to-late 1800s, a heritage still visible in Decorah’s Vesterheim museum and Spillville’s Bily Clocks Museum, which occupies the house where composer Antonin Dvorak spent the summer of 1893.
Getting There
U.S. Route 52 runs north-south through the county’s east side, connecting Decorah toward the Minnesota state line; Iowa Highways 9, 24, 139, and 150 fill out the local network.
- Waukon — 20 miles east
- West Union — 25 miles south
- Cresco — 20 miles west
- Rochester, Minnesota — 55 miles north
The nearest commercial airport is Rochester International Airport (RST) in Minnesota; Amtrak does not serve Winneshiek County, with the closest station in La Crosse, Wisconsin.
Frequently Asked Questions
What is the Decorah postcode?
Decorah’s ZIP code is 52101.
What is the county seat of Winneshiek County?
Decorah is the county seat.
How big is Winneshiek County?
It covers 690 square miles (1,800 km2), almost all of it land.
What was the 2020 census population of Winneshiek County?
It had a population of 20,070 at the 2020 census.
How many townships does Winneshiek County have?
Twenty civil townships, including Decorah, Calmar, Fremont, and Jackson.
What is Winneshiek County known for?
The Driftless Area scenery, Luther College and the Vesterheim museum in Decorah, and Spillville’s Bily Clocks Museum, tied to composer Antonin Dvorak’s 1893 summer stay.
Which counties border Winneshiek County?
Allamakee, Clayton, Fayette, Chickasaw, and Howard counties in Iowa, plus Fillmore and Houston counties in Minnesota.
More counties in this state: Towns and villages in Iowa.