US Senator Edward Kennedy has been buried with military honours close to his assassinated brothers at Arlington National Cemetery in Washington.
The ceremony followed a day of tributes to the patriarch of America's most famous political dynasty.
President Barack Obama, speaking at his funeral in Boston, called the senator the greatest legislator of his time.
The service in Boston was also attended by three former presidents - Jimmy Carter, Bill Clinton and George W Bush.
Senator Kennedy died on Wednesday at the age of 77, from brain cancer.
During a two-day public viewing at the John F Kennedy Presidential Library, some 50,000 people paid their respects before the Massachusetts senator's flag-draped coffin.
At the funeral Mass at the Our Lady of Perpetual Help Basilica in Boston, President Obama paid tribute to his "friend and mentor".
AT THE SCENE
Richard Lister, BBC News, Boston
Music from Yo-Yo Ma set the tone for a sombre occasion which at times had the pomp and ceremony of a state funeral. Before reaching the basilica, the cortege moved slowly through the grey, rain-shrouded Boston streets.
As it did, it passed crowds of people lining up to say their last farewells. Others leaned out of windows some cheering and waving the American flag.
The senator will be buried near his two brothers, who were assassinated in the 1960s. Though many others in the Kennedy family are also in public life, this is widely regarded as the end of an important chapter in America's most famous political dynasty.
He called Senator Kennedy a "kind and tender hero", adding: "He was the soul of the Democratic Party and the lion of the US Senate."
Senator Kennedy's son, Ted Kennedy Jnr, said it had not always been easy living with the Kennedy name but that he was "never more proud of it than today".
In a heartfelt, emotional and at times humorous tribute to his father, he said: "He was not perfect but he believed in redemption. He never stopped trying to right wrongs, whether they were the result of his failings or of ours."
A succession of nieces, nephews and grandchildren also delivered tributes, while cellist Yo-Yo Ma and tenor Placido Domingo both performed at the funeral.
Later, Senator Kennedy's body was flown to Andrews Air Force Base in Washington before transferring to a final motorcade.
Hundreds of people gathered outside the US Capitol - where Senator Kennedy served for nearly five decades - and a brief prayer service was organised for members of the Senate community.
The procession then moved to Arlington National Cemetery, where he was buried close to his assassinated brothers - former President John F Kennedy, killed in 1963, and Senator Robert Kennedy, killed in 1968 while running for president.
Senator Kennedy's family joined in prayers and listened to remembrances from his grandchildren, prior to the burial.
A white-painted oak cross marked the head of his grave and a marble footstone bore the inscription: "Edward Moore Kennedy 1932-2009".
President Obama: "We loved this kind and tender hero"
As the sun set over the cemetery, a volley of three shots rang out and a trumpet sounded a final farewell.
In the US, Senator Kennedy's death has been seen as the end of an era.
Although hailed as one of the most influential US politicians, the senator's career remained blighted by the incident in 1969 when he drove his car off a bridge at Chappaquiddick in Massachusetts.
He fled the scene and a female companion, Mary Jo Kopechne, died.
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