A 65-foot section of the Berlin Wall was accidentally discovered earlier this summer by a group of people on a walking tour.

This week, Berlin gave the newly discovered section status as a protected piece of history to coincide with the the 57th anniversary of the wall’s construction.

In June, Ephraim Gothe, a local politician, set out on a walking tour with a group of constituents. While walking, they discovered a section of the wall hidden underneath vines and covered in a layer of graffiti.

“There can always be new smaller sections hidden somewhere around the city,” a spokesperson for the Berlin Wall Foundation told German newspaper DW.

The newly found section of wall is in a residential zone of northwest Berlin, in the shadow of headquarters for the German intelligence agency BND. The Berlin Wall Foundation believes the section laid undiscovered for so long simply because it did not look like the main section of the wall.

The discovery was part of a “smaller, preliminary wall which separated the death strip from East Berlin,” according to The Local Germany.

“Our experts were able to confirm its authenticity based on the materials used to build it and its measurements,” a spokesperson for the Berlin Wall Foundation told The New York Times. “In addition, there were metal poles protruding from it that were used as lampposts and stones that looked like those from the path that ran through the death strip.”

“I was totally surprised that there were still undiscovered bits,” Gothe told DPA, a German press agency.

East Germany began construction of the wall on August 13, 1961. It was demolished by residents 27 years later on November 9, 1989.