The movements of some long-distance migrants are driven by innate compass headings that they follow on their first migrations (e.g., some birds and insects), whilst the movements of other first time migrants are learnt by following more experienced conspecifics (e.g., baleen whales). However, the overall roles of innate, learnt and social behaviors in driving migration goals in many taxa are poorly understood. To look for evidence of whether migration routes are innate or learnt for sea turtles, here for 42 sites around the World we compare the migration routes of > 400 satellite adults of multiple species of sea turtle with c.45,000 Lagrangian hatchling turtle drift scenarios. In so doing, we show that the migration routes of adult turtles are strongly related to hatchling drift patterns, implying that adult migration goals are learnt through their past experiences dispersing with ocean currents. The diverse migration destinations of adults consistently reflected the diversity in sites they would have encountered as drifting hatchlings. Our findings reveal how a simple mechanism, juvenile passive drift, can explain the ontogeny of some of the longest migrations in the animal kingdom and ensure that adults find suitable foraging sites.