Update (Sunday, Jan 14th, 2024) from Berlin Germany:
Tons of tractors and trucks are arriving. There is a constant stream rolling in and police seems to be overwhelmed. I can't count them anymore.
The streets left and right of Siegessäule are completely packed, they are using alternative streets nearby, but it looks like that isn't enough space.
Currently i estimate between 2k and 3k tractors and trucks!
I'm planning to do a livestream tomorrow at 9a.m. german time (3a.m. EST):
https://www.youtube.com/live/DbMUI9fQ7Vs