Each edition grades its towns against each other only.
More historic than 21% of U.S. towns · #26 of 35 in South Dakota. What drives it
Most of Big Sioux Township was built recently: 6% of its homes predate 1940 and the median home dates from 2003. Below: maps from 1963 on.
The Big Sioux Township post office opened in 1865, the earliest record of the town by name. Two smaller post offices, Big Sioux (1865) and McCook (1873), opened inside today’s town and later closed.
More historic than 21% of U.S. towns, on its age, its old homes and the National Register.
On its age, its old homes and the National Register, Big Sioux Township is more historic than 21% of U.S. towns, #26 of 35 in South Dakota. Its age holds the grade up; its National Register listings pull it down.
South Dakota towns list more on the Register than most of the country (a typical South Dakota town has 37.3 per 10,000 residents, the U.S. 2.4), so Big Sioux Township’s 0.0 sits below most of its state (15% of South Dakota towns have fewer) while its 0 listings outnumber those of 23% of U.S. towns.
Founding year: the first post office (other dates in Quick answers). Homes: Census ACS 2020–24. National Register: National Park Service, May 2026 list; each listing counted once (boundary changes and added documentation belong to their listing), and a historic district counts its contributing buildings. How TownRatings grades history →
Read from the archive, the National Register and the record. The page puts what stands out first.
The first neighbors to add old photos shape how Big Sioux Township’s history is told.
Two other post offices opened and closed inside today’s town.
US Post Offices dataset (Blevins & Helbock, CC0). Places and cemeteries from the USGS Geographic Names Information System (2021).
Wikipedia doesn’t have a history of Big Sioux Township yet. The photos, dates and memories neighbors add here are how it gets written.
Its first post office opened in 1865. Between the 2010 and 2020 censuses its population grew from 3,259 to 4,683 (+44%).
Woven from the archive, old maps, post office records, the National Register and the people born here.
Weddings on Main Street, storms, parades, school pictures, the old store. If it’s in your family album, it belongs here.
Every edition of the U.S. Geological Survey’s map of Big Sioux Township. Tap a year, or press play to watch the town change.
U.S. Geological Survey historical topographic maps (public domain), via Esri’s collection of the scans. The red ring marks the center of Big Sioux Township.
Each neighbor’s History grade, on the same three inputs.
The Big Sioux Township post office opened in 1865, the earliest record of the town by name (U.S. post office records).
Big Sioux Township is more historic than 21% of U.S. towns, #26 of 35 in South Dakota. The History grade combines the town’s founding era, the share of homes built before 1940 and its National Register listings. It’s a character grade, so it isn’t part of the overall grade. How it works.
6% of Big Sioux Township’s homes were built before 1940 (Census estimate, ±4.8 points), against a typical 10% for a South Dakota town; the median home was built in 2003.
What the archives can’t tell you, neighbors can.
Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021).
From U.S. Geological Survey historical maps, the US Post Offices dataset (Blevins & Helbock) and the USGS Geographic Names Information System. Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.
