Swallow arrives in the Europe mid-April, having flown 10,000 km from its winter quarters in southern Africa. The journey takes about four weeks, and males usually arrive first. By early May, most Swallows have started breeding.
By early September, most Swallows are preparing to migrate. They flutter about restlessly, and often gather on telegraph wires. Most leave the UK during September, with early broods of youngsters being the first to go. But a few stragglers may hang around into October.
The return journey to Africa takes about six weeks. Swallows from different parts of Europe fly to different destinations.
Swallows migrate during daylight, flying quite low and at night they roost in huge flocks in reed-beds at traditional stopover spots.
For years people have celebrated their sudden appearance as a sign that summer is on the way.