Part of the activities of the ICT EU Network of Excellence "Building the future Optical Network in Europe" (BONE) project is the development of the European Roadmap on Optical Networking in the context of the "Network of the Future". This paper presents a summary of the views of the BONE consortium as they were developed in the framework of the Roadmap activity. The methodology followed in the development of the BONE Roadmap was firstly to identify and analyse the status of broadband access penetration as well as the availability of specific network and IT technologies in various European countries. The data collected were then processed and translated into the traffic volume (distributed across different European countries) that a Pan-European network would need to support. This information is then used as the basis of a WDM optical network dimensioning exercise performed with the aim of identifying the scale of the required optical network. In addition, based on estimations regarding the evolution of broadband access technologies and the degree of broadband penetration and network services and applications, extrapolations regarding the growth of traffic to be supported by the European Network of the Future were made in a systematic manner. These were also used to dimension and understand the requirements of the European Network of the Future. This paper presents the relevant results and also provides a discussion on the BONE consortium views on the Network of the Future from an architectural and technology perspective and an outlook of the relevant key research challenges and possible solutions.