The first four levels are integrated in Pier H, and above that the tower continues growing to reach its final height of nearly 70 meters. From the fifth level on up, it’s built with the aid of “climbing formwork”. The outer walls of each level are created by pouring concrete directly into the formwork. After the concrete has cured, a 65-meter-tall crane raises it so work can proceed on the next-higher level. To let it reach the upper levels, the crane’s base is gradually raised to a height of 20 meters. The operators then have to do their jobs at a dizzying height with millimeter precision.