Land Artist Hannsjörg Voth’s large-scale projects set up in the Moroccan desert make an impact because of their archaic aesthetic and monumental quality. They are constructed from compressed clay, and thus exposed to deterioration – a crucial aspect of Land Art, which makes art with and in nature, and is subject to natural processes. The building called Goldene Spirale [Golden Spiral], realized in Morocco (Marha-Plane) from 1992 to 1994, is defined by the so-called Golden Section: the ground plan is made up of nine quarter circles whose radii increase on the principle of the Fibonacci series, a numerical sequence in which each number is the sum of the two preceding numbers (1, 2, 3, 5, 8, 13, 21, 34, 55, …). Each triad in this sequence produces an approximation to the value of the Golden Section. Combining the Golden Section with the Fibonacci series is a law that obtains in many natural processes (e.g. in plant inflorescences).