events on the street; happenings in the streets
A somewhat literary set phrase referring to ordinary, everyday incidents that occur in public or among common people.
The newspaper column often covers everyday happenings in the streets.
世間話 refers to casual small talk or gossip, while 市井の出来事 is a more formal, literary expression for actual street-level incidents.
Compound of 市井 (しせい, 'the streets; the town') and 出来事 (できごと, 'event; happening'). The exact historical derivation is uncertain, but the phrase is conventionally used to describe ordinary public occurrences.