During the twentieth century, radionavigation systems created new forms of geographic knowledge that departed radically from the knowledge produced by paper maps. I analyze these systems in two registers. At a macropolitical level, they promoted new kinds of international intervention, from the battles of World War I to GPS-guided humanitarian response. At a micropolitical level, they gave millions of people – pilots, soldiers, anthropologists, teenagers – a newly embedded experience of geographic space. Taken together, I argue that radionavigation offers crucial insight into the history of twentieth-century territoriality and the broad geopolitical shift from the era of internationalism to the era of globalization.