The infamous New Orleans Watermeter cover started being manufactured for the city in 1921. The covers are found in sidewalks all around the city. The design of the cover has become so popular throughout the years with locals and tourists that they have started to disappear. I have heard that if you warm these covers on the stove, they will keep a pot of coffee & chicory warm for hours. The new covers now have a keyhole on them so that they may lock to prevent theft.