It isn’t necessary to walk far from the waterfront to eat amazingly well in Portland, Maine. From a Titanic omelet breakfast at Becky’s Diner or potato dough donut at Holy Donut to Indian pudding ice cream at Beal’s Ice Cream or sea salt chocolate pecan cookies and insanely elegant sticky buns at the Standard Baking Company, Portland’s waterfront is an eager appetite’s playground. But there’s more in this city rich with history and blessed with constant incoming fresh seafood. Among Roadfood favorites are Belgian fries at Duckfat, chili-cheese omelets at Marcy’s Diner, lobster grilled cheese sandwiches at Highroller Lobster, and whoopie pies at Two Fat Cats Bakery. And if you are a hero-sandwich fancier, look in corner groceries for what’s here known as a real Italian — a unique Portland take on the sub.