King Charles and Camilla, the Queen Consort, are travelling in a procession to Westminster Abbey for their Coronation service which begins at 11:00BST (6:00AM EAT).
Thousands of people are lining the route - the umbrellas are out in force, but it's not dampening the party atmosphere of those watching.
Prince Harry has arrived at the Abbey, which is packed with politicians, celebrities, faith leaders and Commonwealth representatives.
Meanwhile, leading members of Republic, the anti-monarchy group, are among half a dozen people arrested near Trafalgar Square.
After the service, there will be a second, larger procession before a royal appearance on the Palace balcony.
Watch the event live on BBC.
