At the Beginning Was a Drawing Board, at the End is the Metro

We started more than 50 years ago. The designs for the first metro lines were conceived at the drawing board, in work clothes, with a drawing pen and a slide rule. There was a revolution in design technology due to the advent of computers in the 1990s. The chance to modify a finished design without using a rubber was probably the most visible change on the outside. However, there was also an important contribution hidden in the speeding up and refinement of structural calculations, of which a considerable amount are needed in this type of underground construction. And nowadays? We still print drawings, but they are created as a by-product of the design, which is processed as a three-dimensional model of the structure.