BERLIN — Chancellor Angela Merkel and former Soviet leader Mikhail Gorbachev crossed a former fortified border on Monday to cheers of "Gorby! Gorby!" as a throng of grateful Germans recalled the night 20 years ago that the Berlin Wall gave way to their desire for freedom and unity.

Within moments of a confused announcement on Nov. 9, 1989 that East Germany was lifting travel restrictions, hundreds of people streamed into the enclave that was West Berlin, marking a pivotal moment in the collapse of communism in Europe.

Merkel, who grew up in East Germany and was one of thousands to cross that night, recalled that "before the joy of freedom came, many people suffered."

She lauded Gorbachev, with whom she shared an umbrella amid a crush of hundreds, eager for a glimpse of the man many still consider a hero for his role in pushing reform in the Soviet Union.

"We always knew that something had to happen there so that more could change here," she said.

"You made this possible — you courageously let things happen, and that was much more than we could expect," she told Gorbachev in front of several hundred people gathered in light drizzle on the bridge over railway lines.

Tears sprang to the eyes of Uwe Kross, a 65-year old retiree, who recalled seeing the start of the drama on Nov. 9, 1989 from his home, a block away from the bridge.

"That night, you couldn't stop people," Kross said. "They lifted the barrier and everyone poured through.

"We saw it first on TV, normally it was very quiet up here, but that night we could hear the footsteps of those crossing, tap, tap, tap."

Kross was among those who crossed early on — so early that nobody was yet waiting on the other side when they reached the West. He recalled hopping on the first subway to then-West Berlin's main boulevard, the Kurfuerstendamm.

"All hell was breaking loose there," Kross said.

Merkel also welcomed Poland's 1980s pro-democracy leader, Lech Walesa, to the former crossing Monday, saying that his Solidarity movement provided "incredible encouragement" to East Germans.

The leaders were joined by prominent former East Germans such as Joachim Gauck, an ex-pastor who later oversaw the archives of East Germany's secret police, the Stasi.

"Those in government thought they were opening a valve, but once it was open much more happened," Gauck said of the border opening. "A collapse followed."

The bridge crossing was one of a series of events marking Monday's anniversary of the border's opening after the wall kept East German citizens penned in for 28 years.