On the four-hour train ride from Frankfurt to Berlin, my daughter, the friends we had come to visit and I used our phones and the helpful Marco Polo guidebook we had purchased at the Frankfurt station to plan the two brief days we would be there. By the time we pulled into the station, we were ready to go. After checking into our hotel, we began with a centralized overview of the city so that we could narrow down what we most wanted to explore more fully. By booking a hotel in the Spandauer Vorstadt area we were walking distance to Alexanderplatz, where the Fernsehturm, Berlin’s great silver orb, towers over the city. There, we were able to get tickets to a hop-on-hop-off bus tour that provided information around many of the important sites in the city—including a drive past some of the remaining sections of the once-divisive Berlin Wall. …