Colleges — how this layer is made

What you are looking at

Each point is a college — a feature tagged `amenity=college` in OpenStreetMap. 68,899 of them worldwide, drawn as a coloured dot sized by footprint area and coloured by who operates it, where that has been recorded. At the closest zooms the dot is joined by the building's or campus's mapped outline, where one has been drawn.

Click any college to see what OpenStreetMap records about it — its sector, and the body that runs it where a mapper recorded that. Where the college has a Wikipedia article, a short summary is fetched live and shown in your own language; and every college links to the OpenStreetMap object it came from.

Universities and schools have their own layers, and places of education shows every level together.

What a "college" is

This is the map's biggest caveat, and it is about the word rather than the data. `amenity=college` is OpenStreetMap's tag for post-secondary further education: education after school but distinct from a university. In the UK that is a sixth-form college or a further-education college; in the United States it often means a community college; elsewhere it covers technical institutes, teacher-training colleges and agricultural colleges. In some countries the word "college" is used for a secondary school, and in others for a university — so the tag does not mean what a reader's own country's usage would suggest.

What is on this map is what mappers tagged as `amenity=college`. Comparing two countries says as much about how each names its institutions, and how its mappers tag them, as about the institutions themselves.

Mapped, not modelled

Each college is an object a mapper drew, from survey, local knowledge or aerial imagery; nothing here is modelled or estimated. The limitation is therefore completeness, not resolution: an unmapped college is absent, and on this map absence looks identical to empty ground.

Colour, and how much of it there is

Colour shows who operates the college — and only about one college in ten says. The rest are drawn in grey.

Not recorded — 90.4% of colleges
Privately operated — 4.5%
Publicly operated — 4.4%
Religious — 0.3%

Grey is a real, named category on this map. It says nobody has recorded who runs that college, not that the college is unusual.

"Privately operated" does not mean "charges fees". OpenStreetMap's tag says the operator is a non-government body — a company, a trust, a charity. Many such institutions are publicly funded and free to attend. The legend says "operated" throughout for that reason, and the schools layer leaves the tag out altogether, because for schools the gap between the two meanings is wide enough to mislead about real named places.

Size

Each symbol is sized by footprint area — the ground the mapped outline covers, in square metres measured on the globe. Symbol area is proportional to footprint (radius to its square root), so a college four times the area draws twice as wide.

Many colleges are mapped as a single point, with no outline and so no footprint. Rather than draw them all at the smallest size, they are given a nominal, typical size a little below the median footprint. Whether a college is mapped as a point or an outline is mostly a matter of how thoroughly it was mapped.

Footprint is physical extent, not enrolment or standing. An agricultural college with fields draws larger than a city institution with more students and one building.

Completeness

OpenStreetMap is not equally complete everywhere. Coverage is strongest in Western and Central Europe and other well-mapped regions, and thinner in low- and middle-income countries. An absent college means "not yet mapped", not "does not exist". A dense patch here is a well-mapped place first.

A picture of the present

Today's map, not a history. OpenStreetMap is edited continuously; this copy is refreshed periodically. There is no year control, and a college closed or merged long ago may still be mapped until a mapper updates it.