Middlesex County, Massachusetts Map with Towns and Population

How to use this map

This is Middlesex County, drawn as the 54 cities and towns it is divided into. Pick a map type along the top: Cities and towns colours them so no two neighbours share a fill, Density shades them by people per square kilometre, Satellite swaps the flat colours for aerial imagery, and Blank outline gives you black on white for printing. Click any town, or any row in the table, for its population, land area and density.

Switch between metric and imperial with the Units control. Everything on the page follows it, including the downloads.

What this county is made of

Middlesex County held 1,632,002 people at the 2020 Census across 2,118 square kilometres of land, which works out at 770.4 people per square kilometre. Its seat is Cambridge. Within Massachusetts it is first by population out of 14 and third by land area, holding 23.2 percent of the state.

The 54 cities and towns on this map are the units the county is actually administered through, and they cover every square metre of it. Cambridge is the largest at 118,403 people, and Ashby the smallest at 3,193.

The cities and towns add up to 1,631,966 against a published county figure of 1,632,002, a difference of 36. That gap comes from the sources rather than the map: county totals here are Census Bureau figures, while the individual town counts are the published municipal ones, and the two are revised on different schedules. It is worth stating rather than hiding, because a table that reconciles perfectly is usually a table that has been forced.

Where the data comes from

Boundaries and land areas come from the United States Census Bureau through the TIGERweb service. County populations are 2020 Census counts. The county seat comes from the published county list for Massachusetts.

Aerial imagery, and how it is fitted to the map

The Satellite map type replaces the flat colours with real aerial imagery from the United States Geological Survey, taken from The National Map. Most of it comes from the National Agriculture Imagery Program, flown at one metre resolution or better.

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 right for a whole country but turns to mush over a single county. At one metre you can pick out reservoirs, the road network, the line where development gives way to woodland, and the shape of built up areas within each town.

The imagery arrives as a plain latitude and longitude grid while this map is drawn in Lambert conformal conic, so every pixel is converted back to a latitude and longitude and the matching pixel is read from the source. Both then sit in the same projection, which is why the boundaries follow the ground instead of drifting away from it.

The imagery is public domain, as work of the United States government. The credit is drawn onto the map itself so it travels with the image when you download it.

A check you can repeat on paper

Take Cambridge, the largest town here.

The published figures give it 118,403 people and 16.6 square kilometres of land. Divide one by the other and you get 7145.6 people per square kilometre.

Select it on the map and the Selection panel reads the same figure. Add the 54 land areas in the table and they come to 2,118 square kilometres, the published land area of Middlesex County.

Mistakes that catch people out

Treating the drawn area as land. The county outline includes its inland water, and here the boundary encloses about 3 percent more area than the land figure. Density on this page is always computed on land.

Confusing the county with the place that shares its name. Cambridge is the seat of Middlesex County, not the whole of it, and the county contains 53 other cities and towns besides.

Mixing census years. Every population here is 2020. Figures from a later estimate will not reconcile against anything on this page.

Related Calculators and Reference

• Massachusetts County Map: all 14 counties of Massachusetts with population, land area and density.
• United States Map: all fifty states, with a county map behind each one.
• United States Census Bureau, Geography: the source of the boundaries and land areas used here.
• The National Map viewer: the USGS browser behind the aerial imagery on this page.

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.