DUNKIN' DONUTS. When it comes to donuts and coffee at Mainz Central Station, our quality is unbeatable. That’s because we’ve been in business since 1950 and have been constantly improving. Back then, Bill Rosenberg opened our first store in Quincy, Massachusetts, USA. Today, we’re proud to be the world’s largest bakery and coffee chain, with over 11,000 stores worldwide, and to make more than five million customers around the globe happy every day. In addition to specialty coffees, we offer over 30 different varieties of donuts, muffins, brownies, and cookies, as well as savory bagels, sandwiches, soft drinks, and much more.