Because attendees had to get to the church early, there was plenty of time for socializing.
There were a good amount of across-the-aisle conversations as well, like this one between former CIA Director John Brennan, left, and White House Chief of Staff John Kelly, right.
Just before the ceremony started, President Trump and First Lady Melania took their seats.
They were greeted by the Obamas, who were seated between the Trumps and Clintons.
next slide will load in 15 secondsSkip AdSkip AdThe first pew of the church was filled with all the living presidents and their wives.
Former President George W. Bush and former First Lady Laura Bush stood outside the cathedral to salute the president's casket as it arrived.