Rockport - May not be "Open"
One word of caution if you're looking to Rockport as an overnight. I did a delivery on my boat in May 4th a few years back from Newburyport to Marblehead. My wife was seasick, so we dropped her off in Rockport for her sis to pick her. There were no docks or support folks until May 15th. We had to swing in and drop her of onto a wooden ladder from the street.
You maybe able to find an empty mooring inside the breakwater or anchor outside the harbor, but be prepared to have your own means of going ashore. You may want to call the harbormaster a day or too before your trip and get the status.
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