the first leg
The first stage or part of something. I did well for the first leg of the race, but then my muscles started cramping up. Whose brilliant idea was it to start the first leg of our journey with a 4 AM flight?
first leg (of a journey)
and the first leg (of the journey)the first segment of a journey; the first flight of a multiflight trip. The first leg of the journey got me to London.