Since the beginning of the 'reception crisis' in 2015, the term 'solidarity' has been widely employed in Europe by networks supporting migrants in transit. These networks - while increasingly important and prominent in contemporary Europe − are still understudied and have only recently been addressed in migration studies. The research takes place in two crucial border zones: on the one hand, the island of Lampedusa, which is a sea point of entry into Europe through Italy; on the other, the Susa Valley, an alpine point of exit from Italy that allows the passage to France. How are the solidarity networks put together? How do they interact with the mobility practices of migrants in transit? How do the practices of solidarity fit in with the ways authorities act at the border? The ethnographic fieldwork was developed in the middle of the COVID-19 pandemic and aims to answer these interconnected research questions.