Keystone is a term which in regard to the field of architecture refers to the crucial stone at the top of an arch, the stone that keeps the structure locked in place. The part and the whole have been in focus in this workshop, that has been organised and taught by Michael and Desie from Studio Elements. The students have been asked to shape their own basic architectural elements, base, pillars, walls and roof in aerated concrete and assemble them to a minor house with three rooms and a covered outdoor space. Finally all the models were placed together forming a “white city” guided by the consideration of the quality of the spaces created between the houses and the infrastructure.