Typical of many Paris doors from the 19th century, the details of the stone architecture are unique in design and frame beautifully the well-preserved heavy doors. The cart belongs to the postman (le facteur) to transport the mail as s/he walks the neighborhood. The ornamental wrought iron piece at the foot of a door is called a "chasse-roue" and was a practical implement to protect the door or gate from the carriage wheels. You will see them all over Paris, some of wrought iron as seen here, and others of stone. It would be interesting to photograph a collection of the different designs.
Rue de Lyon