New series of Spain's capital stock and input are constructed for the last one-and-a-half centuries. Capital stock and input grew at average rates of 3.5 and 3.7 percent per year but not at a steady pace since rates accelerated dramatically during the 'Golden Age'. Two major structural changes accompanied this process. Composition of capital stock and remuneration changed gradually as the contribution of productive capital rose while that of structures declined. Spanish economy experienced capital deepening in the long-run. Although the capital-output ratio increased over time, in phases of accelerated growth the productivity of capital rose.