The Wall Tours of Berlin focuses on many major points along the former border in the center of Berlin.
With close inspection, one can get to see the cynical remains of this man made structure, which has disappeared. Other than that, through guided tours, one can get to know the horrifying historic background of the wall.
The tour even offers visits to the museum where there are display of this events picturised. Then there is also historical film and sound clips shown to the tourists.