On May 1, 1971, Mayor Samuel Zoll proclaimed it “Hello Day.” Fire station bells rang across Salem at noon. Residents poured into the streets — along Essex Street, across the Common — to do something radical in its simplicity: say hello to each other.

A rock band made up of Salem High students played on the Common. A conceptual artist circled overhead in a plane, photographing the whole thing from above. Channel 5 showed up. A teenager named Marian Sonier told the Salem Evening News it was the best time she’d had in months.

Salem did this two years before the rest of the world even had the idea.

Now Salem turns 400, and we’re bringing it back.