Every Resident of Delaware Lives Within 100 Miles of Dover — Yes, All of Them

By SimpleMapLab·Published 13 May 2026·Rank #2 of 50 states·↑ All 50 states

Every resident of Delaware lives within 100 miles of Dover. Delaware is one of the four US states physically small enough to be fully enclosed by a 100-mile circle drawn from its capital.

A 100-mile geodesic radius around the Dover, DE state capitol overlaid on Delaware. 100.0% of Delaware's population lives inside the dashed ring.

100.0%

of Delaware’s population within 100 miles of Dover

1.02 M

residents inside the radius (of 1.02 M statewide)

11 mi

from Dover to Delaware’s population centroid

of 50 states ranked by capital-to-population centrality

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

Why this happened

Dover sits in the middle of Delaware's three-county geography (New Castle to the north, Kent in the middle, Sussex to the south). The state is so compact that the 100-mile radius from Dover envelops not only every resident but also significant portions of Maryland, southern New Jersey, and southeastern Pennsylvania. Delaware's three counties have separate political identities but share a single capital reach.

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 Dover. Cities are listed by total population captured by ZIP centroids in the dataset.

#	City	Population in radius
1	Wilmington	222,353
2	Newark	141,898
3	Dover	76,581
4	New Castle	62,392
5	Middletown	53,234

How Delaware compares

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

#1 Connecticut

Hartford · 100.0% pop. captured

#3 New Jersey

Trenton · 100.0% pop. captured

#4 Rhode Island

Providence · 100.0% pop. captured

#5 Vermont

Montpelier · 98.6% pop. captured

#6 Maryland

Annapolis · 98.4% pop. captured

Draw it yourself

Open the 100-mile circle around Dover →

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 Dover’s reach with that of Wilmington, or add a second circle for a side-by-side comparison.

Methodology (brief)

We took the lat/lng of the Delaware state capitol building (39.1582°, -75.5244°) and drew a 100-mile geodesic radius. For every ZIP code in Delaware, we tested whether the ZIP centroid falls inside; if so, its population counts. We then divide by Delaware’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 Dover: How Much of Delaware Is Inside? Part of the State Capital Radius study. Retrieved from https://www.simplemaplab.com/studies/state-capital-radius/delaware. Licensed under CC-BY 4.0.