Marietta Diner is on Cobb Parkway. Unfortunately, that large sign across the front of the building doesn't face the highway, so it won't be as easy to spot as you may think. The space inside is large, bustling, and comfortable.
But I was disappointed to make a quick trip to the restroom just after ordering and coming back to discover that my table, including my drink and appetizer, had been cleared. This isn't the sort of thing that makes diners feel welcome.