Exploration #142. The Humboldt substation, together with the Kottbusser Ufer and Wilhelmsruh substations, forms a group of buildings designed in the mid-1920s by architects Hans Heinrich Müller and Felix Thümen for Berliner Städtische Elektrizitätswerke AG (BEWAG). A distribution substation transfers power from the transmission system to the distribution system of an area. It is uneconomical to directly connect electricity consumers to the main transmission network, unless they use large amounts of power, so the distribution station reduces voltage to a level suitable for local distribution. Each building was reserved for one function: switcher room, power factor correction room, transformer room and control room. This was located in a separate building in the centre of the complex in its inner courtyard. The Humboldt substation served northern Berlin as an electrical transformer station until 1993. Since then, the buildings have been designated as a protected monument by the city of Berlin. Since 2015, the digital marketing company Glispa together with the companies Movinga, Quandoo and Hometogo, have moved their headquarters to the complex now known as ‘Ampere’. The beautiful, perfectly preserved control room has now been converted as a social entertainment space for the employees of the Glipsa company.