This is a photograph — not a postcard — of Main Street in Rockport. It comes from the collection of old postcards and photos belonging to Merry Seppala of Rockport. I estimate the date to be around 1930, based on the models of cars.
The scene looks east on Main Street. The building to the left was replaced by the Shalin Liu Performance Center. The lawn to the right is the front of the Congregational Church. The building on the right, behind the girl on the sidewalk, housed the Granite Shore Inn and, directly on the corner, the Post Office. Down the street, a police officer stops traffic as a dapperly dressed couple crosses the street.
Merry does not know who took this picture. She has several pictures taken by Charles Cleaves, to whom she was related, but does not know if this was his.
Note that the trolley tracks have disappeared from Main Street in this photo. You can seem them in earlier pictures, such as this one from 1920. The trolley stopped running in 1920, as I’ve previously noted.