R2CITIES aims to develop and demonstrate an open and easily replicable strategy for designing, constructing, and managing large scale district renovation projects for achieving nearly zero energy cities. For this purpose, it will be developed a demonstration and dissemination framework of very innovative strategies and solutions for building energy renovation at district level, based in the following pillars:• Three demonstrations of residential district retrofitting, in different countries, climate conditions, user’s habits, etc.• A very ambitious dissemination programme focused on public and professional audiences.• Several studies of cost-effective solutions for the holistic improvement of the energy performance of buildings at district level (definition of standard indicators and new diagnosis approach, analysis of existing energy technologies in a systemic approach, new strategies for urban energy planning, …)• Deployment of a rigorous measurement and verification of energy performance and savings plan for each demonstration, taking into account standard protocols as IPMVP.• A market and replication deployment plan, in order to ensure the project impact at business level, and a results exploitation strategy suitable for achieve a wide impact.3 demo sites will be addressed for demonstrating the framework and associated impacts by developing real cases going beyond current market standards but ensuring the replicability of the concepts deployed. R2CITIES makes a difference from current state of the art, as it will be far away from current expensive and stand alone pilots that have failed into reaching the market. Valladolid, Genoa and Kartal (Itanbul) municipalities will provide three demo sites for a very ambitious renovation of three residential districts, involving more than 65.000 m2, more than 700 dwellings and more than 1500 users, with a potential of energy consumption reduction near to 60 %.