 The Romans only began to achieve significant originality in architecture around the beginning of the Imperial period, after they had combined aspects of their original Etruscan architecture with others taken from Greece, including most elements of the style we now call classical architecture.They moved from trabeated construction mostly based on columns and lintels to one based on massive walls, punctuated by arches, and later domes, both of which greatly developed under the Romans.The classical orders now became largely decorative rather than structural, except in colonnades.