In the realm of things few are more charged with meanings than ruins. They dissect the material world so violently that in its cracks fresh perspectives have repeatedly been discovered. And so ruins have always provoked an interest of painters and school kids, philosophers, and even botanists. Paradoxically the obvious creator of every ruin, the architect, rarely showed any interest in this inevitable renegade creation of his. In my article I first explore the various approaches different epochs showed towards the notion of a ruin just so I can then attempt to subtract the historical, political and philosophical charges and look at the ruin as at a material and truly architectural object. Ruin is a product of conflict between the order and chaos, total and fragmented, regular and accidental. It is this conflict that produces accidents, exceptions and points of friction at all possible levels and scales. This understanding of a ruin as a fragile point of balance between two conflicting states relates it closely to the concept of Weakness in Architecture as described by Juhani Pallasmaa and Ignasi de Sola Morales. In my article I propose a dual identity between the ruin and the concept of weak architecture, upon which fresh starting points for architectural practice can be constructed.