Swallows start arriving in Europe at the end of March. They spend their winter in South Africa and usually return to the same district and even the same nest where they settled before. The female lays four to five eggs, white with reddish brown speckles. She sits on them for about 15 days before they hatch out. Both parents then feed the nestlings with insects which they catch while flying. Swallows usually lay two sets of eggs.
Swallows build their nest inside farm buildings and on ledges in old chimneys. The nest is made of mud straw and saliva, with feathers and wool to line the inside. It takes a pair of swallows ups to several weeks to make the saucer shaped nest in the rafters of a barn.
They leave for their winter location in September, gathering in large flocks before setting off. The young swallows of the first brood leave before their parents and, by an inborn knowledge, know where to go.