The idea for De Groene Kathedraal (The Green Cathedral), a project by Marinus Boezem (Leerdam, 1934) stems from 1978. Boezem wanted to realize this landart project in an artificial landscape, in which changes in time and space are clearly visible. The polder to the south of Almere proved to be a good spot. In April 1987 the project was begun and 178 Italian poplars were planted in the form of an outline of Notre Dame of Reims…