Press and data

Ancient Trees maps the oldest and most remarkable trees of the world's cities, one tree at a time, with sources recorded per tree. 790 trees in 148 cities across 33 countries so far, 203 distinct species, 790 of them carrying their sources on the page.

The story, and where to check it

The London plane, which we map 64 times in 35 cities, is a chance hybrid of an American and an Asian parent that appeared in a nursery in the 1600s and became the default street tree of half the continent. The individual arrivals are better than the statistic: an ombu in Seville said to have come back from South America with Christopher Columbus's son around 1529, a black locust in Paris grown from seed posted out of the Appalachians in 1601, a black mulberry in London left over from a royal scheme to start a British silk industry that failed because silkworms will not eat black mulberry leaves.

The full list, with locations and sources for each tree: Europe's Oldest City Trees Are Mostly Immigrants.

Other angles in the same data

Which city gives the best afternoon, measured by how many remarkable trees stand within one walk of each other rather than by how many a city has: Europe's best tree city trips. The oldest tree in each country we cover: the oldest tree in every country we map. Every tree on one map: explore, or by city.

Images

328 of the 790 trees carry a photograph under an open licence, most from Wikimedia Commons and iNaturalist. Each one records its licence and the credit that licence requires, both shown on the tree's own page. The credit has to travel with the image: a CC BY photograph published without its attribution puts the licence in breach, and that is the publisher's problem rather than the photographer's. Trees without a photograph show a drawing and say plainly that no photograph exists, because a stock picture of the species would not be a picture of that tree.

What this data is, and what it is not

It is a count of the trees we have published, not a census of every old tree in Europe. The map is denser where countries publish open tree registers and thinner where they do not, so coverage reflects data availability as much as it reflects trees. Ages are as sourced, and where sources disagree the tree's page says so rather than picking a winner. Locations are marked either confirmed or approximate, and the approximate ones say so next to the directions button, because sending someone to a spot where the tree is not is the one mistake this project cannot afford.

Getting in touch

For the underlying data as a spreadsheet, a count for one country or one city, or anything else: send a message and say what you need.