How to identify a building from a photo

There are two completely different versions of this problem, and confusing them is why people give up. Identifying the Colosseum from a photo is trivial — it is one of the most photographed objects on Earth. Identifying the handsome brick building at the end of your street is hard, because almost nobody has photographed it and written down what it is.

The methods below are ordered by what they are actually good at, not by how well known they are. Most people try the first one, fail, and stop — when the second and third would have worked.

Why reverse image search fails on ordinary buildings

Reverse image search matches your photo against other photos. It does not know about buildings; it knows about pictures that resemble each other. For a landmark with millions of indexed images and a Wikipedia article attached, that resemblance is enough to return a name. For a 1930s apartment block that has been photographed four times, there is nothing to resemble.

This is the single most useful thing to understand. The moment a building is not famous, image similarity stops being the right tool, and the question becomes geographic: what stands at these coordinates?

The five methods, and what each one is for

1. Google Lens — for landmarks and distinctive facades

Open the photo in Google Lens (built into the Google app, Google Photos, and Android's camera). It is the strongest general-purpose option and handles anything with a reasonable photographic footprint: cathedrals, towers, famous museums, unusual modern architecture. It also occasionally surprises you on a minor building if that building happens to appear in a real-estate listing or a tourism page.

2. Visual Look Up — for landmarks, without leaving the Photos app

On an iPhone running iOS 15 or later, open a photo and tap the info button. If Apple recognises a landmark, a small star appears on the icon and tapping it gives you the name and a short description. The coverage is narrower than Lens and it is landmarks only, but it is instant and works on photos already in your library.

3. OpenStreetMap — for ordinary buildings, by location

This is the method most people have never tried, and it is the one that works on your street. OpenStreetMap contributors tag individual buildings with a name, a construction date, an architect, and a heritage reference. Find the building on the map, click it, and read the tags. In dense European cities the coverage is far better than you would expect.

Look specifically for the wikidata or wikipedia tag. If one is present, it is a direct link to everything formally recorded about that building.

4. National heritage registers — for protected buildings

Every country with a preservation system keeps a searchable list, and these lists are exhaustive in a way that crowdsourced data is not. If a building is protected, it is in one of them, with a date, an architect, and usually a paragraph of history:

• France — base Mérimée, the Ministry of Culture's architectural heritage database, covering monuments historiques.
• United Kingdom — the National Heritage List for England, plus the equivalent registers for Scotland, Wales and Northern Ireland.
• United States — the National Register of Historic Places, searchable by county and by address.
• Italy, Spain, Germany and most of the EU maintain regional equivalents, usually at the province or Land level.

5. The building itself

Before any of the above: look up. Date stones above doorways, architects' signatures carved into the base of a facade, blue plaques, and the small enamel plates that French and Belgian cities fix to notable buildings will all answer the question in about four seconds. Photograph the plaque, not just the building.

A practical order to try them

1. 01Look for a plaque or date stone on the facade. Fastest possible answer.
2. 02Run the photo through Google Lens. If the building is at all notable, you are done.
3. 03If Lens fails, switch from image to location: find the building on OpenStreetMap and read its tags.
4. 04If the tags are empty but the building looks protected, search the national heritage register for that street.
5. 05Still nothing? Search the street name plus a decade in the municipal archive — most city archives are digitised and indexed by address.

What to do when nothing matches

Sometimes the honest answer is that a building has no recorded history, because most buildings do not. A speculative apartment block from 1962 may never have been written about by anyone. In that case the useful record is the street, not the structure: municipal archives, old street directories, and historic maps will tell you what stood there before, who built the block, and why the street bends the way it does.

Doing it in one step

Globo is built around the gap described above: it uses your photo and your location together, so it is not limited to buildings that happen to be photographed often. You point your camera at what is in front of you, and it returns the place, its history, and an audio version you can listen to while you keep walking.