On April 15, 2019, a fire started in Notre-Dame de Paris and caused significant damage.  In its honor, here is a bonus episode on the great cathedral.

We know that Notre Dame will survive this calamity, because it has survived other calamities before.  From Baroque refacing to revolutionary desecrations, Notre Dame had become an absolute wreck. Then Victor Hugo's novel started a restoration movement which led to the appointment of Eugène Viollet-le-Duc, whose detailed work created the church we've grown to love.

Beyond talking about the cathedral, we have sidebars about post-war Poland (it makes sense; trust me) and the Montparnasse neighborhood.

Finally, we link to the narrative by discussing the Muslim conquest of Spain and the Battle of Tours (or Poitiers) in 732, setting the stage for the next three episodes.

Sources:

Eyewitness Travel Paris

Hollis, Edward. The Secret Lives of Buildings

Horne, Alistair. Seven Lives of Paris

Rick Steves Paris

Robb, Graham. Parisians: an Adventure History of Paris

Winston, Richard and Clara. Notre-Dame de Paris