Krzysztof the Oak

Poznan's oldest protected tree on this page stands inside a playground fence, which is not where you would expect to find a tree the city dates to as much as three centuries old. The oak took its name, Krzysztof, from Anna Siwczyk, a local artist who helped restore the square around it before her death in 2010, and the name has stuck deeply enough that in 2023 the city's greenery authority grew a batch of seedlings from its acorns and nicknamed them the Krzysztofy. Trunk circumference runs to 375 centimetres, and an arborist's report at designation put its age between 250 and 300 years and assessed it in very good health with full mechanical resistance, a formal way of saying the wood inside is sound. The council made it a natural monument in late 2017 or early 2018, depending on whether the date used is the register's or the city's own announcement of the vote. The fence around it belongs to the playground it stands in, run by Poznan's Municipal Greenery Authority and open during ordinary hours, not a barrier put up to keep visitors out. It borders a building used by a local Alzheimer's association, but the ground itself is public, in the Wilda district, a genuine enclave of old growth in one of the city's more built-up corners.