It's called Chartres Blue. It is a blue that is unrivaled in any stained glass in the world. Just a 40 minute trip from Paris, The cathedral stands out as a medieval skyline on the french plains as you approach the town.
Group 3 - Early Medieval Gothic Architecture│ The church is grand and tall. There are several pointed arches which the middle one is the tallest. In the right corner of the picture, you can see the vaulted ceiling. Many ornate decorations are added.