Ever wondered what the places around you looked like in the past?

French art director Julien Knez wondered the same thing as he walked around Paris, and spent the summer of 2015 taking photos of famous Parisian sites while holding up vintage photos of what they used to look like in front of the lens.

The result is a photo book, "Paris, Fenêtres Sur l'Histoire," which contains 80 images of modern Parisian streets overlaid with old photographs that reveal what the French capital looked like over 100 years ago.

Knez worked with photos he found from between 1871 and 1968, bringing key moments from Paris' history — such as the great flood of 1910 and Hitler's visit to the city in 1940 — into its present.

Check out a selection of photos from his book below, arranged in chronological order.

Words by Chloe Pantazi at Insider