The wall didn't just divide Berlin, it also split an entire nation. Tens of thousands of people lived within close distance of the border area, with the security barrier, barbed wire and cement walls in sight. Many of these small towns and villages have changed dramatically during the two decades since German reunification. Bridges now cross rivers that were exclusion zones during GDR times. Trains now whiz through areas once patrolled by soldiers, and areas once blighted by a cement barriers blocking both freedom and a view have been opened to reveal panoramic vistas.
East Germany decided to upgrade the fortifications in the late 1960s to establish a "modern frontier" that would be far more difficult to cross. Barbed-wire fences were replaced with harder-to-climb expanded metal barriers; directional anti-personnel mines and anti-vehicle ditches blocked the movement of people and vehicles; tripwires and electric signals helped guards to detect escapees; all-weather patrol roads enabled rapid access to any point along the border; and wooden guard towers were replaced with prefabricated concrete towers and observation bunkers.