to come and go; to go back and forth
祭りの日、大勢の観光客が街を行き交った。
On the day of the festival, many tourists came and went through the streets.
繁華街では朝から晩まで人が行き交っている。
People come and go in the busy shopping district from morning to night.
港では毎日多くの漁船が行き交う。
Many fishing boats come and go in the harbor every day.