The patterns of scientific cooperation between the 28 European Union (EU) member countries, Switzerland and Norway, from 1993 and 2017, are evaluated in this article. We consider co-authorship patterns to be proxies for international transfers of tacit knowledge. The theoretical part of the paper contains propositions by researchers in evolutionary economic geography on path-dependence, selection and variation, and the role of networks in knowledge transfer. The principal argument is that the geographical configurations of knowledge transfers over distance are shaped via a set of connectivities – specific communication channels for the exchange of people, goods and knowledge between two or more countries. Some connectivities are more conducive for the transfer of explicit knowledge (e.g. merchandise trade, trade in patents), while human exchange flows (students, migrants, travellers) favour the transfer of tacit knowledge. The research project found that a considerable increase in human exchanges has helped to increase the total number of co-authored papers, but did not amend the geography of the European co-authorship network over last two decades. Rather, the layout of the network stems from a relatively stable set of historical, cultural and political legacies in Europe.