At first glance, you might think I took this photo of a little medieval castle somewhere in France.

But no — I found this remarkable fortified gate in the heart of Paris last week, during a walk through the Marais.

It is the gate of the Hôtel de Clisson, built in the 14th century, and one of those extraordinary reminders that Paris still hides fragments of its medieval past in plain sight.

Right in the middle of the city. Right in the Marais. Incredible, isn’t it?