There is just as much history underground as above ground in Berlin. Berliner Unterwelten shows you the history, where the sun never shines.
Checkpoint Charlie is a tourist trap, but it is still an experience to see the historic border crossing where World War III nearly broke out in 1961.
The Chapel of Reconciliation stands as a memorial to the victims of the Berlin Wall and the Reconciliation Church, which was demolished in 1985.
The sculpture in Invalidenpark is a memorial to Gnadenkirche, where war heroes were buried. And in memory of the reunification of Germany.
The East Side Gallery is an open-air gallery stretching over 1 kilometer, painted on the remains of the Berlin Wall from Ostbahnhof to Oberbaumbrücke.