The west-facing façade of the cathedral in Amiens is made up of three intricately carved portals.
This is a slideshow featuring close-up shots of some architectural details. I believethat these bas-relief carvings
date back to the time when the cathedral was built in the 13th century.
In the image below, you can see the intricacy of the carvings. The images in the slideshow are some of those that are surrounded by four-leaf clover shapes.