As the royal couple left, they chatted with students from St. Paul's School on the cathedral steps, The Guardian reported.
The church, at the heart of the old City of London, was designed by Sir Christopher Wren to replace the cathedral destroyed in the Great Fire of London. Construction began in 1675, and June 21, 1711, was officially declared the day of completion -- partly because Wren was supposed to receive the balance owed him six months after finishing work.
During World War II, the cathedral survived German raids aimed at its destruction. Wren, Samuel Johnson, the duke of Wellington, and Adm. Horatio Nelson are among those buried there.
"The much overworked word 'iconic' has been used to describe the dome, and no one could fail to recognize its silhouette," the Right Rev. Graeme Knowles, dean of St. Paul's, told the congregation. "The wartime photographs of the dome rising unscathed above the smoke and fire of the blitz can be found everywhere."
Knowles also commented on the appropriateness of Wren's epitaph: "Lector si monumentum requieris, circumspice," Latin for "Reader, if you seek a monument, look around you."