The three works on display here are part of a larger whole: the installation at Portikus in Frankfurt showed seven of the nine pieces in the Solid Maneuvers series. Along with the drawing The Apparatus (2015), these works also refer to the damage caused to landscapes and people.

The inspiration for this work came when Nkanga undertook a study tour along one of the railroads in Namibia. Her endpoint was the town of Tsumeb.  Since 1875, this place is known as the 'Green Hill' because of the very rich substrate containing copper ores, with the copper soils becoming green from oxidation. Initially, the ores were used by the original population (the San or Bushmen) as trading goods with neighbouring populations like the Ovambo, who transformed them. In 1905, the discovery of copper stocks by the West led to the founding of the town of Tsumeb by the German colonial power in Africa and shortly after, the railway was built to facilitate the draining of resources: 243 different types of minerals were extracted from the Tsumeb mines. In the late 1990s, the deepest mine was closed: economically, it was no longer viable, since most raw materials were already extracted.

During her trip, Nkanga did not end up in the land of the Green Hill, but in a desolate and ruined, completely emptied landscape, a deep wound which only through its bareness, it's 'lacking', still referred to the once rich soil. The copper had long been extracted, shipped, processed and used to add lustre to European steeples. Every connection to their origin has been erased – or not? With her exhibition at Portikus, Nkanga sought an opportunity to reinterpret these mined holes as underground monuments and to regard the use and 'residence' copper received in Europe –  topping architecture – as a pedestal for the minerals.