Carroll County, New Hampshire Map with Towns and Land Area
| County | Population | Land area | Polygon area | Difference | Density | Share of county |
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Boundaries and land area: United States Census Bureau, TIGERweb, public domain. Population: 2020 Census of Population and Housing. Aerial imagery: United States Geological Survey, The National Map, public domain.
How to use this map
The map opens on the Divisions view with all 19 of Carroll County’s municipalities drawn straight from Census boundary files. Click any one to pin it and read its figures: land area in square kilometres, 2020 population and the density that falls out of those two. The tabs above the map change what the shading means. Divisions gives each unit its own colour so you can tell neighbours apart at a glance. Land area shades by size. Satellite drops one metre aerial imagery under the boundaries. Blank outline strips the fill away for printing or tracing.
The figure people misread is land area. Census land area excludes water, so a municipality with a lake or a river frontage looks smaller in the table than it does on the map. Moultonborough is the clearest case here: its boundary encloses 194.07 square kilometres but only 154.59 of that is land, leaving 39.48 as water. If you are measuring something that sits on the ground, use the land figure. If you are measuring something that follows the boundary, use the polygon.
What this county is made of
Carroll County holds 18 towns, 1 location. Sandwich is the largest by land area at 235.37 square kilometres and Hale's the smallest at 6.44, which makes the largest roughly 36.5 times the size of the smallest. The median sits at 124.22 square kilometres, so the spread is wide but most units cluster nearer the middle than the extremes.
Ossipee is the county seat, which is the New England term for what the rest of the country calls a county seat. Conway is the largest by population at 9,822, about 20 per cent of the county total. Conway is the densest at 54.6 people per square kilometre and Hart's Location the emptiest at 1.4, a ratio of about 39 to one. Hart's Location has 68 people.
Across the whole county the density is 20.7 people per square kilometre. That is the number to hold on to, because it explains the shape of the map: a few dense nodes and a long tail of thinly settled ground, with the average describing almost none of the individual units.
Where the data comes from
Boundaries come from the Census Bureau TIGERweb county subdivision layer, which is the authoritative source for municipal geography in New Hampshire. Land area is the Census land measurement, which excludes inland water. Population is the 2020 Decennial Census count for each municipality.
The sources are joined on municipality name, and that join is worth checking rather than trusting. The 19 land areas sum to 2,413.53 square kilometres against a published county land area of 2,413.55, which agrees to the hundredth. 1 of the 19 units are unincorporated townships, grants and purchases with no published municipal population, so they appear on the map without a population figure. The 18 with published figures sum to 49,975 against a published total of 50,107, a difference of 132 people. Both figures are given here rather than adjusting either one.
Aerial imagery, and how it is fitted to the map
The Satellite tab pulls one metre aerial imagery from the USGS National Map. One metre means each pixel covers roughly a square metre of ground, so at full zoom you can pick out individual buildings, field boundaries and the line of a farm track. That resolution matters at this scale. The national and state maps on this site use a NASA composite at five hundred metres per pixel, which is fine for showing where New Hampshire sits in the country and useless for showing where a municipal line runs.
The boundaries are drawn in an Albers equal area projection fitted to this county, with standard parallels set inside its own latitude range. Equal area matters here because the map is shaded by area: if the projection distorted area, the shading would be lying. The imagery arrives in Web Mercator and is reprojected to match.
A check you can repeat on paper
Take Ossipee. Its land area is 182.53 square kilometres and its 2020 population is 4,372. Divide 4,372 by 182.53 and you get 23.95 people per square kilometre, which is what the panel shows rounded to 24.
Now check it against the county. Ossipee holds 8.7 per cent of the 49,975 people on 7.6 per cent of the 2,413.53 square kilometres. That gap between population share and land share is the whole story of the map in one comparison.
Mistakes that catch people out
Reading polygon area as land area. The map draws boundaries, and boundaries include water. This county encloses 2,568.1 square kilometres of polygon against 2,413.53 of land, so 154.57 is water, about 6 per cent.
Assuming a city is bigger than a town. In New Hampshire those words describe charter type, not size. Hale's location is the smallest unit here at 6.44 square kilometres.
Expecting the average to describe a unit. At 20.7 per square kilometre the county average sits between Hart's Location at 1.4 and Conway at 54.6, and matches neither.
Assuming municipal lines follow roads or rivers. Many were surveyed as charter grants or survey townships long before the roads existed. The straight lines on this map are the original survey, not modern infrastructure.
Related Calculators and Reference
- New Hampshire County Map, for all 10 counties and where Carroll sits among them
- United States Map, for the national view and how New Hampshire compares
- Massachusetts County Map, for the same treatment applied to another New England state
- US Census Bureau Geography, the source for boundaries, land area and population
