I arrive in Berlin on a Tuesday in June. My plane arrives at 11:25 and I have the rest of the afternoon/evening free. It is the only day during my trip that I haven't already planned. I would appreciate tips on interesting things that I can do in half a day in Berlin. Is it worth it to try to get to Potsdam, which I understand is a 20 minute train ride from the Zoo train station? I'm not sure what time everything closes there.
20 minutes doesn't sound right... I didn't time it on my watch, but I would say an hour is closer to it. I assume Park Sanssouci is your foucs, and you would have to grab a bus to even get there. I don't see you realisitically arriving any earlier than 3. Everything closes at 6, which isn't much time to explore, much less visit some of the palaces.
What else have you planned in Berlin?
We are only there for 2 1/2 days. We are taking the Discover Berlin walking tour with Berlin Walks on our first full day there and we will decide which sites we want to go back to. We also have reservations to visit the Reichstag and the Dome.
The second full day, we are taking a tour of Third Reich sites.
Is there a way you could take your introductory walking tour on the afternoon you arrive? That would work out much better. Then, the next day you could go to Potsdam or could spend more time seeing the city, and your last day could be the Third Reich tour.
I see in June they have introductory two tours a day, but the second one is at 1:30 PM (from the western starting point at Zoo station) or 2 PM (from the eastern starting point at Hackescher Markt station). Depending on whether your plane is on time, and where your hotel is, you may or may not be able to make those times.