This application shows the first made CAD model of the former clock of the Notre-Dame cathedral in Paris. This clock was destroyed by the April 15, 2019 fire, but a survey had been made in 2016. Based on this survey, a CAD model was made in 2020, and this 3D application in 2021. It makes it possible to examine the clock and to animate the going work. This is the first application of this kind.