Photo Gallery Obama in Berlin

US Democratic presidential candidate Barack Obama delivered his keynote speech on trans-Atlantic relations in Berlin on Thursday.

He spoke to over 200,000 people who had thronged around the historic Victory Columnm, in the center of Berlin.

The speech, which was the only public one on his European tour, was hugely anticipated.

Obama urged Europeans and the US to come together again after having drifted apart. He said they needed to work together to defeat terror and to "dry up the well of extremism."

Obama's appearance in Berlin had the feeling of a rock concert. The Democratic politician is extremely popular in Germany: a large majority of Germans would like to see him become the next president.

In his speech Obama also called on people around the world to look at Berlin and the way it had kept the "dream of freedom" alive.

He told the crowd it was time for Americans and Europeans to tear down walls that divided allies, races and religious communities.

After the speech, Obama greeted some of the hundreds of thousands who had turned up to hear him speak.

Despite admiring Obama's gifts as a speaker, some of the crowd thought the speech was aimed less at them than at TV audiences in the US. As the speech was also short on specifics, Obama's critics are likely to accuse him of empty rhetoric.

Obama had flown into Berlin from Israel earlier on Thursday to start the European leg of his overseas campaign trip.

The Democratic senator began his visit to the German capital with a stop at the Chancellery to meet with Chancellor Angela Merkel.

Merkel had expressed doubts about Obama's original plan to hold a vast public speech in front of the Brandenburg Gate. But she said on Wednesday that she was excited to meet the candidate.

While in Israel, Obama sought to reassure the country of his commitment to America's "historical" relationship with the Israelis. Prior to jetting off to Berlin, Obama prayed at the Western Wall in Jerusalem before dawn.

Chancellor Merkel's spokesman Ulrich Wilhelm said that Merkel and Obama had "very open" and far-reaching talks, according to the Associated Press.

Wilhelm added the two talked about foreign policy, including Iran, Afghanistan, Pakistan and the Middle East. The trans-Atlantic economic partnership was also part of their chat.

The talks between Germany's leader and Obama lasted about an hour.

After the meeting the senator and his entourage traveled about a half mile from the Chancellery to Hotel Adlon, Berlin's most famous hotel.

Berlin has been awaiting the Obama visit for weeks. He is staying at the Hotel Adlon, right next to the Brandenburg Gate, which is ironically the site where he originally wanted to speak.

Hundreds gathered at the entrance to the Adlon to get a glimpse of the presidential candidate. But he went in the back door.

There was a brief scare at the hotel on Thursday when a suspicious package was found in the lobby. It turned out to be a book.

Tourist attraction: Two actors, dressed in US military uniform and holding the American flag, pose in front of the Brandenburg Gate.

Obamafest: Left a traditional badge, right one based on an October Fest motif.

Helicopters have been clattering over the heart of Berlin all afternoon. Security is tight for the visit.

Heavy security: Obama's convoy is made up of 20 vehicles and around 700 German police are protecting the US politician during his trip in Berlin.

When Obama steps to the microphone on Thursday evening in Berlin, he is expected to ask Europe to do more in hotspots around the world. Obama has said that Afghanistan would be a priority of his presidency, should he be elected.

Lonely voice: A man carries an umbrella decorated with McCain posters at the Brandenburg Gate.

A supporter of Barack Obama outside the Hotel Adlon in Berlin on Thursday.

In the afternoon Obama met with German Foreign Minister Frank-Walter Steinmeier, who later said he detected parallels in their foreign policy philosophies.

Obama also met with Berlin's mayor Klaus Wowereit, who presented him a porcelain bear, the city's symbol.

Obama also signed the city's official guest registry: "Thank you to the mayor of this great city."

The morning already saw the media setting up around the Victory Column, where Obama will deliver his much-anticipated speech. Pundits are questioning whether his speech can live up to expectations.

Lobbying groups and NGOs used the opportunity of the senator's visit for a bit of publicity. Here, WWF protesters dressed up as polar bears to help call attention to the dangers of climate change.

Huge numbers of people descended on Berlin's Fan Mile, hoping for a good vantage spot to watch Obama's speech.