We needed to pick up tickets for a concert that night so we decided to walk to the ticket office. We ended up giving ourselves a walking tour of the city. We walked and walked and walked. Side note, you can't always trust the expected walking time when using google maps. During our walk we saw the following attractions: Holocaust Memorial, Reichstag Dome, Sony Center, and the Brandenburg Gate.
That evening we went to an outdoor concert at the Waldbuhne. We saw the Berliner Philharmonic featuring Renee Fleming. We had a great time listening to amazing classical music while enjoying the beautiful scenery around us. We particularly enjoyed the traditional encore piece. The audience jumps to their feet (many with sparklers in hand) and sings and whistles along with the orchestra. It was fantastic!
The next morning we went to the East Side Gallery. This is an open air art gallery on the longest stretch of the Berlin Wall. The murals are filled with various political statements and are very artistic.