ARPANET’s story is part of the Internet’s official heritage, as a first crucial step in its development. Janet Abbate’s seminal work Inventing the Internet (1999) has extensively covered its history and is still a landmark in this area. However, the 50th anniversary of ARPANET provides an opportunity to reflect on existing histories and to open up the debate to new perspectives and approaches. If we consider ARPANET as a first step towards the Internet, how did it determine – and how does it continue to determine – our current understanding of the Internet? What is left to explore and discover in ARPANET’s history? And if ARPANET is dead today, are its legacy and spirit still alive, and if so, in what way?