Decided to end this year with some suffering (seemed appropriate). I haven't felt really fit recently and this is the longest run I've ever attempted, so this went about as terrible as expected. Felt hard from halfway through, was forced to take a lot of walking breaks, but pushed through.
I started and finished at Frankfurter Allee, way later than I had intended. I almost missed the closing time for the Tempelhofer Feld (make sure you keep in mind that they close it when it's dark if you go for this!) Brought some snacks and water in a backpack, so luckily I could go without resupplying, even though there would be plenty of opportunities to do so. (And temptations to quit and take the S-Bahn instead..) Rain started about 30km in, to add to the darkness..
Didn't exactly get a good run, so this stays a very beatable Fkt - I think if you really want to set a perfect time, aside from being a better runner than me (which is easy), I'd recommend going early in the morning to avoid traffic and pedestrians.