The Temple of Venus and Rome and Santa Francesca Romana at the Roman Forum : preservation and transformation The first architecture : from the Velia to the Vestibule of the Golden House of Nero The place transformed : the Temple of Venus and Rome of Hadrian Decadence destruction and recovery of the place : the Churches of Ss. Peter and Paul and S. Maria Nova and Alexander III Architectural preservation and transformation patronage and innovation : the Olivetan Benedictine Monks Carlo Lambardi and Gianlorenzo Bernini The new conservation ideology : Giuseppe Valadier and Giuseppe Camporese Conservation and architectural project: Giacomo Boni as pioneer of the Critical Conservation Conclusions : the architectural conservation project : preservation and transformation.