* Magnetic compasses: Swallows have a small organ in their heads that acts like a magnetic compass. This organ helps them to sense the Earth's magnetic field and use it to navigate their way home.
* Landmarks: Swallows also use landmarks to help them navigate. They may remember certain buildings, trees, or other objects along their migration route and use them as markers to help them find their way back home.
* Sun: Swallows also use the sun to help them navigate. They may watch the position of the sun in the sky and use it to determine their direction of travel.
In addition to these physical cues, swallows also use a form of "cultural transmission" to learn their migration routes. This means that they learn about the routes from their parents and other adult swallows. This helps them to avoid making the same mistakes that previous generations of swallows have made and ensures that they are able to find their way home from migration.