In January 1924, Flemish avant-garde magazine Het Overzicht published a list of its congenial modernist for­ma­tions named ‘Het Netwerk’. It named nineteen magazines from Europe, the United States and Brazil, including the Polish magazine Zwrotnica. It exemplified the close and direct relationships within the supranational network of the avant-garde. Various formations belonging to this network, both bigger and smaller nodes, were linked to each other, often directly through befriended artists and writers. It did not only concern places such as Paris or Berlin, but also less pivotal nodes of the avant-garde network. In this paper I will present a case study of two countries, namely Poland and Belgium, as an example of European interwar cultural mobility. Joined in their pursuit of modern art, and crossing national and linguistic frontiers, Polish, French and Dutch-language magazines exchanged and re-printed each other’s texts and artworks, a practice also discussed in the correspondence between their representatives. Based on such tangible traces I will describe the cultural mobility and mutual exchange between the Polish and Belgian modernist journals, and attempt to shed light on the features, dynamics, and key figures of the network.