BERLIN — “It was a very touching moment. It brought back memories of a time when as a young man I had sworn to fight the wall.”

Those were the words of Carl-Wolfgang Holzapfel, a 73-year-old retiree who says that he helped dig a tunnel under the Berlin Wall in the 1960s.

The entrance to the tunnel, a desperate attempt to pierce the Iron Curtain and reunite a divided family, was unearthed this week after laying hidden for more than 50 years.

The discovery has fueled memories of a dark chapter in Berlin’s history.

Filled in and forgotten

When East Germany sealed off its section of Berlin in August 1961, many families and friends were separated. Shortly after, a group of four West Berliners, responding to the call of a man named Gerhard Weinstein, found an abandoned railway shed near the wall that split their city, and began digging.