During the bombing of 1940, the old telephone building was partially spared, as was the nearby library and part of the savings bank. Part of it was already restored during the war for important telephone traffic. On December 4, 1951, the new telephony building at Botersloot is officially opened. The building was designed by architect J. Koops, who works for the Department of Public Works. Due to scarcity of materials, construction had taken longer than planned. Due to the visual art applications of sculptor Joan Bakker, the building was seen as a PTT building (PTT was the predecessor of KPN). The wide entrance area above the main entrance contains the letters PTT and a symbolic representation of the role that the PTT played in the world. The left side depicts the harbor and the water. On the right we see the land, the harvest and two horses' heads. Under the letters PTT we see a telephone receiver and an electricity pole. The bolts from the mast not only represent electricity, but also the energy of that time, of the Reconstruction and the way in which Rotterdam was built. Bakker had a tough job, because Swedish granite was a difficult material. He worked in a cage on the building for three months. It is the hardest type of stone and therefore the relief has not become very strong, but when the light strikes it, it is very beautiful and the shapes speak for themselves (according to a report in the Rotterdam Newspaper in 1950). This also applies to a number of facing bricks that Bakker made for the same building. One stone shows two lashing figures. This represents cable laying, the construction of the telephone network after the war, which is an important symbol of progress. The relief has beautiful lines that are hard and graceful at the same time. It used to be a decorative edge, but after a renovation it was placed at street level in the courtyard. Another facing brick is still located at a height of 24 meters above the entrance. It probably depicts Mercury, the god of trade, riding a dolphin, the symbol of the ocean.
