If you're looking to eat like a local and enjoy a wide variety of options, this is the place for you. I visited downtown Frankfurt and stopped here on a walking tour. I came back later in the afternoon on my own for more time to explore. Schreiber is my top recommendation. The owner has been making the sausage and mustard by hand for 60 years. From butchers to fresh produce, pasteries to ready made meals, the market has plenty to offer anyone. There are also free public restrooms.