I don't know why the North Shore of Boston is the heart of "roast beef sandwich" territory, but it is. Among the best are at Village Roast Beef. The absolute nicest family runs it too. I'm not even much of a red meat eater, but I find their roast beef sandwiches on a soft bun with their bbq sauce practically irresistible. And if you're hankering for something sweet, someone in this wonderful Greek family bakes an perfect Baklava that you can buy by the piece at the counter.