The Ginkgo of the Humboldt University Courtyard

The Humboldt University keeps two protected ginkgos, one in each of its courtyards, and Berlin registers them as two separate natural monuments. This is the southern one, Naturdenkmal 1-6/B-1. Its twin, 1-6/B-2, stands about 60 metres to the north, in the other courtyard of the same building. Berlin listed both on 2 March 1993. The reasons depend on who you ask. The state register gives beauty and regional heritage. The Wikipedia list of natural monuments in Mitte gives rarity and distinctiveness. That makes four reasons across two sources, and not one of them is age. The moment to come is November. A ginkgo's whole crown turns butter gold and then drops its leaves in a day or two, so the window is short and easy to miss. The tree also starts a short walk. A protected red horse chestnut stands in the forecourt a few steps away, and a protected London plane grows on Bebelplatz across the street, so three of Berlin's natural monuments sit within a couple of hundred metres of each other. University courtyards are normally open by day, but we have not confirmed the hours, so check at the gate. Nobody has published an age or a girth for this ginkgo. If you have a tape measure and a minute, tell us what it comes to.