Mayor Bill de Blasio was part of the group at Adam Clayton Powell Boulevard on Friday morning.
The mural will stretch across the boulevard from 125th and 127th Streets. Local artists and members of community groups will paint the words “Black Lives Matter” on both sides of the median, so the phrase can be read by anyone heading north or south.
RELATED STORY: Work On Fifth Avenue Black Lives Matter Mural Postponed
Artists will spend the weekend putting the finishing touches on the mural in Harlem.