Night train to Amsterdam

Tomorrow we travel to Amsterdam. We have to check out of the hotel at 11:00. We will take our bags to the train station and put them in a locker. Then we will have to entertain ourselves for the day. Maybe a walking tour or a bike tour. We can decide in the morning. I know we will repeat some things we have seen, but it will be helpful to have a tour guide. We would also like to spend some time in Tiergarten, Berlin's Central Park. Our train leaves at 00:16. I'm used to staying up that late, but not being out that late dragging around a huge backpack. I am looking forward to the night train experience after watching Alfred Hitchcock's North by Northwest when I was a child. Hope I can sleep.