The project Network of Letters (NETLET) has three main aims: 1) to develop and implement digital tools for data processing, analysing and visualising large correspondence collections; 2) to build the base for an online national data repository that will store metadata and data of large correspondence collections of intellectual elites from the Bohemian/Czech lands focusing on three periods of national and general history (1580–1670, 1870–1939 and 1939– 1989); 3) to analyse the collected metadata (several thousand items) of the three large correspondence collections related to the three periods by methods of network analysis and to visualise these data using digital visualisation tools developed during the project. Doing so, it will get a better understanding of the Bohemian/Czech lands and their elites position within national, European and global communication networks.