The Most Misplaced US Capitals: Pierre Reaches 10.8% of South Dakota, Sioux Falls Is 189 Miles Out

By SimpleMapLab·Published 13 May 2026·Rank #48 of 50 states·↑ All 50 states

Only 10.8% of South Dakota’s population lives within 100 miles of Pierre. The state’s largest population centre — Sioux Falls — sits 189 miles from the capital, far outside the 100-mile circle. South Dakota ranks #48 of 50 states for capital centrality, meaning 2 states have a less-misplaced capital.

A 100-mile geodesic radius around the Pierre, SD state capitol overlaid on South Dakota. 10.8% of South Dakota's population lives inside the dashed ring.

10.8%

of South Dakota’s population within 100 miles of Pierre

97 K

residents inside the radius (of 897 K statewide)

74 mi

from Pierre to South Dakota’s population centroid

#48

of 50 states ranked by capital-to-population centrality

Open this radius in the map → /tools/map-radius-tool · Pierre, SD · 100 mi
The link opens the SimpleMapLab Map Radius Tool with the 100-mile circle already drawn around the Pierre capitol. Change the radius to 50, 250, or any value to compare different framings.

Why this happened

Pierre, South Dakota was chosen in 1889 not for its population centrality but for its location: roughly the geographic midpoint of the new state, accessible by Missouri River steamboat. The compromise location lost relevance as railroads bypassed it and population shifted east toward Sioux Falls and Rapid City. Today Pierre is one of the smallest state capitals in America (population ~14,000) and reaches just 10.8% of South Dakotans within a 100-mile radius.

Sioux Falls, the state's largest city by a factor of ten, sits 189 miles east of Pierre. Rapid City, the second-largest, sits 170 miles west. Neither falls inside the capital's 100-mile circle. South Dakota's political geography is effectively split between two metro areas neither of which can reach the capital in under three hours.

The biggest cities inside the 100-mile radius

The top 5 most-populous places (by aggregated ZIP code population) sitting inside the 100-mile circle around Pierre. Cities are listed by total population captured by ZIP centroids in the dataset.

#	City	Population in radius
1	Pierre	17,326
2	Winner	4,386
3	Eagle Butte	3,775
4	Mission	3,740
5	Mobridge	3,422

The largest city outside the radius

South Dakota’s most-populous city outside the 100-mile circle is Sioux Falls, sitting 189 miles from Pierre. The aggregated population of Sioux Falls’s ZIP codes alone — 208,064 residents — illustrates the gap between South Dakota’s political seat and its population centre.

How South Dakota compares

The states ranked closest to South Dakota on this metric. Click any to compare the radius breakdown directly.

#47 New York

Albany · 14.7% pop. captured

#49 Alaska

Juneau · 6.2% pop. captured

#46 Illinois

Springfield · 19.1% pop. captured

#50 Florida

Tallahassee · 3.9% pop. captured

#45 Texas

Austin · 21.3% pop. captured

Draw it yourself

Open the 100-mile circle around Pierre →

The Map Radius Tool lets you change the radius (try 50 mi for an urban-suburban question or 250 mi for “a day’s drive”), drag the centre to compare Pierre’s reach with that of Pierre, or add a second circle for a side-by-side comparison.

Methodology (brief)

We took the lat/lng of the South Dakota state capitol building (44.3683°, -100.3510°) and drew a 100-mile geodesic radius. For every ZIP code in South Dakota, we tested whether the ZIP centroid falls inside; if so, its population counts. We then divide by South Dakota’s total population to produce the percentage. The full methodology for all 50 states is on the hub page.

Suggested citation: SimpleMapLab (2026). 100 Miles Around Pierre: How Much of South Dakota Is Inside? Part of the State Capital Radius study. Retrieved from https://www.simplemaplab.com/studies/state-capital-radius/south-dakota. Licensed under CC-BY 4.0.