How can a juvenile songbird fly alone, following the same route as its parents across thousands of kilometres of sea, deserts and mountain ranges until safely arriving to its wintering grounds? Migratory songbirds perform long, individual flights, often across continents. This complex behaviour is genetically inherited and it is defined by several physiological, behavioural and morphological adaptations. However, the mechanisms and identity of these genes are largely unknown due to their complex, entangled effects. Furthermore, population and individual-level differences in the migration tracks difficult the study of this trait. In my PhD project I intend to shed some light into this field. By combining molecular techniques such as qPCR analyses and karyotyping with bioinformatic analyses and fieldwork (tagging wild passerines with light-level geolocators), I will gain a better understanding on how birds find their way to wintering grounds and back.