What to know about the queen’s lying in state in Westminster

FILE - Britain's Prime Minister Tony Blair, front right, leader of the Liberal Democrats Charles Kennedy, front second right, Iain Duncan-Smith, the leader of the Conservative Party and Deputy Prime Minister John Prescott, front left, file past officers from the Household Cavalry standing in vigil at the coffin of Britain's Queen Elizabeth the Queen Mother as it lies in state in Westminster Hall in London Friday, April 5, 2002. Hundreds of thousands of people are expected to flock to London’s medieval Westminster Hall from Wednesday, Sept. 14, 2022, to pay their respects to Queen Elizabeth II, whose coffin will lie in state for four days until her funeral on Monday. (AP Photo/Santiago Lyon/Pool, File)