(AP) President Barack Obama should have felt right at home in his overnight visit to Germany, with summer weather that felt more like Washington than Berlin.
Average highs are normally in the 70s in Germany's capital city in June, but they were in the 90s Tuesday as Obama spoke at the historic Brandenburg Gate nearly 50 years after President John F. Kennedy's famous cold war speech there.
German Chancellor Angela Merkel introduced Obama from a stage with no cover for the bright hot sun. "We've chosen the best possible weather to welcome you most warmly, as it were," she said.
"It's so warm," Obama replied, "and I feel so good, that I'm actually going to take off my jacket and anybody else who wants to, feel free to."
The crowd of 4,500 broke into cheers, after waiting for hours under tight security that prohibited them from bringing in water bottles. The Red Cross said 104 people were treated at the site for dehydration and sunburn, although fortunately none were ill enough to require hospital treatment.
Berlin Mayor Klaus Wowereit, sitting behind Obama on the stage, took the president up on the invitation to dress down.
"We can be a little more informal among friends," Obama said.
The weather wasn't all that felt familiar to the president.
As Obama and German President Joachim Gauck greeted children waving flags from their two countries at Bellevue Palace, German photographers repeatedly shouted for Obama to turn toward them so they could get a better picture.
"The press is the same everywhere," Obama quipped.
Obama told his audience at the Brandenburg Gate that his family's absence at the speech was not a slight to Berlin, but to him.
"The last thing they want to do is to listen to another speech from me, so they're out experiencing the beauty and the history of Berlin," Obama said.
First lady Michelle Obama and daughters Sasha and Malia visited monuments commemorating dark eras of the country's past. They were joined by the president's half sister Auma, who went to university in Germany and flew in to meet them from her home in Kenya.
The family walked through the Holocaust memorial, a vast undulating field of more than 2,700 gray concrete slabs designed by American architect Peter Eisenman. The monument to the 6 million Jews killed by the Nazis was opened in 2005 next to the U.S. Embassy and the site of the bunker where Adolf Hitler committed suicide.
Merkel's husband, chemistry professor Joachim Sauer, made a rare public appearance to show the Obamas one of the few remaining sections of the Berlin Wall, which East Germany's communist rulers built in 1961 and divided the city until 1989. Sauer, like Merkel, grew up behind the wall in the communist east.
The first lady and her daughters placed yellow roses in the gaps between the concrete slabs of the wall's main memorial.
The first family stayed at the Ritz Carlton on the glitzy Potsdamer Platz, which was largely a vacant lot throughout the Cold War with the wall running right through it, just a few feet from where the hotel now stands.
Obama paid tribute in his Brandenburg Gate speech to the "airlift of hope" that kept West Berlin out of Soviet hands in the late 1940s and to a 92-year-old veteran of the operation once known as the Candy Bomber.
Gail Halvorsen was among the crowd that braved the heat to hear the president's speech. He got his nickname for air-dropping handkerchief-tethered chocolate and gum to the children of Berlin. "He and his comrades made it possible for the city to survive," said Mayor Wowereit.
The airlift began on June 26, 1948, in an ambitious plan to feed and supply West Berlin after the Soviets blockaded the city, attempting to squeeze the U.S., Britain and France out of the enclave within Soviet-occupied eastern Germany. American and allied pilots flew 278,000 flights to Berlin over 15 months, bringing in food, coal, medicine and other supplies. The Soviets realized in 1949 that the blockade was futile and lifted their barricades.
Obama said the United States couldn't be prouder of Air Force veteran Halvorsen. "I hope I look that good, by the way, when I'm 92," the president said.
Germany and the United States both could claim some credit for a spectacular warm-up act by violinist David Garrett before Obama's speech.
Garrett, the son of a German father and an American mother, was born and raised in Aachen on German's western border and studied at Julliard in New York under famed Israeli-American violinist Itzhak Perlman.
Garrett performed songs by Obama favorite Bruce Springsteen and German composer Ludwig van Beethoven.
He also performed his version of "Smooth Criminal" by Michael Jackson, who infamously dangled his baby outside a hotel window just up the street.
Associated Press writers Robert H. Reid and Frank Jordans contributed to this report.