Kim Hjelmgaard, USA TODAY
LONDON -- The United Kingdom steeled itself and said a final formal farewell to the Iron Lady, the former Prime Minister Margaret Thatcher, who presided over the nation during a period of huge economic and social change from 1979 to 1990.
Over 4,000 police were deployed in central London amid heightened security concerns in the wake of the Boston Marathon bombings this week, and ahead of the London Marathon on Sunday when over 36,000 runners will take to the city's streets.
Thatcher's coffin was carried in a horse-drawn gun carriage from the Royal Air Force chapel of St. Clement Danes on the Strand to St. Paul's Cathedral, a 20-minute journey of just over a mile through the heart of the capital.
Spectators lining the route broke into applause - and scattered boos - as the carriage passed by, escorted by young soldiers, sailors and airmen.
More than 700 soldiers, sailors and air force personnel lined the route taken by Thatcher's coffin to the cathedral and around 4,000 police officers were on duty.
About 2,300 dignitaries, friends, ex-colleagues and family members attended her service at St Paul's including Queen Elizabeth II and her husband, the Duke of Edinburgh. Former Vice President Dick Cheney and former secretary of State Henry A. Kissinger were also present. George Shultz and James Baker represented President Obama's official delegation. Former Prime Minister Tony Blair attended, as did F.W. de Klerk, the former president of South Africa.
Ahead of the service, current Prime Minister David Cameron told BBC radio, "We are all Thatcherites now." He spoke of her deep impact on British public life but also of her status as a source of division.
"She was the first woman prime minister. She served for longer in the job that anyone for 150 years. She achieved some extraordinary things in her life. I think what is happening today is absolutely fitting and right," Cameron said, referring to controversy over the scale of today's event.
Mourners at St. Paul's, a Church of England cethedral dating to the late 17th century, entered to music by British composers including Edward Elgar and Ralph Vaughan Williams. The service featured hymns and readings chosen by Thatcher, who grew up as a grocer's daughter in a Methodist household.
Her 19-year-old granddaughter Amanda Thatcher read a passage from Ephesians: "Stand therefore, having your loins girt about with truth, and having on the breastplate of righteousness."
The dean of St. Paul's, David Ison, recalled "her courage, her steadfastness and her resolve to accomplish what she believed to be right for the common good."
Before the service, Thatcher's coffin was driven from the Houses of Parliament to the church of St. Clement Danes for prayers.
From there the coffin - draped in a Union flag and topped with white roses and a note from her children reading "Beloved mother, always in our hearts" - was borne on a gun carriage drawn by six black horses from the Royal Horse Artillery to the cathedral.
The funeral of Thatcher in format resembled that of Diana, Princess of Wales. It was a ceremonial funeral with military honors, essentially one step down from a full state funeral, which is normally reserved for the sovereign as head of state.
In many respects, though, today's service was very similar to a full state funeral. For example, it is the first time a British monarch has been present at the funeral of a British prime minister since the death of Sir Winston Churchill in 1965.
"I liked Thatcher. She was good for the self-employed," said Martin, 50, a contractor from London who watched the procession as it neared St Paul's. He did not want to share his last name. "Taxes were high when she was in power but she gave us the chance. She did a lot for people like me."
As a mark of respect, one of London's most recognizable sights, the bell on the Big Ben clock tower of the Palace of Westminster, remained silent throughout the proceedings. With the exception of a deliberate outage during World War II, the bell has rarely been silenced since its inception in 1859.
Immediately outside St Paul's, the British penchant for quiet reserve held sway as an eerie calm prevailed while Thatcher's coffin was carried up the steps of the cathedral. Some spectators further down the processional route at the start of Fleet Street turned their backs at Thatcher's coffin, and the funeral cortège, as it passed by, but the protests were in keeping with what London's Metropolitan Police had forecast: Low-key.
David Walsham, a drama teacher from Somerset, in south west England, said he would have preferred a "more modest funeral." In his view, Thatcher "legitimized greed," and "put in place a legacy we are still suffering from." He mentioned the large-scale privatization of the U.K's utility industries.
Walsham said that he prefers not to speak about Thatcher with his students, who range in age from 11 to 18, because he "gets too worked up."
Earlier, the route to St Paul's was lined by hundreds of military personnel from the three armed forces. After departing St Clement Danes, the procession traveled along Fleet Street and up Ludgate Hill. Thatcher's coffin was draped in the Union Flag.
At Thatcher's request, military units with a connection to the 1982 Falklands War were heavily represented.
APPRECIATION: Foe of unionism, communism, Thatcher made her mark in Britain
REACTION: Thatcher remembered as tough and controversial
While no official estimates for the cost of the funeral have been released, several media reports suggested that the total expense could surpass the $15 million mark.
Following her death from a stroke on April 8, at 87, Thatcher's legacy has been the subject of intense domestic debate, with many of her supporters and detractors here at odds about how best to mark the occasion.
"Today, don't turn on your TV or radio, no paper, off the Twitter feed. Let her 'go in peace.' Let her go in 'abject disregard,'" wrote Tom Gray, a musician from Brighton, in a tweet.
But Thatcher is the subject of massive international interest and many in the crowd had traveled to bear witness to today's proceedings.
Margaret Kittle, 79, told the Press Association news agency that she had come all the way from Canada for the funeral. "I always said I would come because I respect her," she said. "I think she did a lot for the world."
The Right Reverend Richard Chartres, who presided over the funeral service at St Paul's, told the congregation that "today is neither the time nor the place" for politics.