The Fleischman Viaduct crosses the Unterer Adlitzgroben, a wide, slanting, valley with a damp floor. Therefore, the laying of the foundations for the viaduct had to be particularly deep. The viaduct itself, however, was built too lightly. Because of the wet underground and the lateral thrust of the train operations it did not take long before the first cracks appeared. The viaduct had to be reinforced. The pillars on the outer side of the viaduct (the opposite side from this view) were given support pillars and the vault was fortified by inner rings. Generally speaking, the viaducts of the Semmering Railway were massively built, and have, up to present, stood up well to the pressures of traffic.