
Today is a big day for Berlin - January 26, 1244 is the date recorded on the oldest existing document with the name Berlin mentioned in writing: it is a deed signed by Margraves Johann and Otto and by “Provost of Berlin” Symeon in a tax-related dispute between the Margraves and Brandenburgian bishops (who-pays-what-to-whom-and-when were the traditional grounds for such conflicts, and remain so until today).
Even though the deed names the year 1244, Berlin’s 750th birthday was celebrated in both East and West Berlin not in 1994 but in 1987. How come?
Because today’s Berlin has its roots not in one but in two settlements (trade settlements, mind you - not “organically” grown hamlets) and Cölln, Berlin’s sister-city on whose grounds Berlin’s Stadtschloß was built, got its first written mention already in 1237. In another deed - like the 1244 also co-signed by the same Symeon (albeit featured here not as Provost but as Symeon plebanus de Colonia).

With the 1237 deed having been signed on October 28, Berlin’s official birthday is celebrated in autumn.
Of course, both Berlin and Cölln were evidently older than 1237 and 1244 respectively. It is simply that all earlier written records were most likely lost in repeatedly occurring fires of both cities’ town halls.
To find your way around the 13th-century Berlin, here’s a helpful 1839 map by K.F. Klöden - one of the best tools today as all central objects were subtly superimposed onto the plan of the old sister cities. Enjoy exploring!
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