The biggest Starbucks store is in Chicago.Grace Dean/Business InsiderStarbucks' biggest store is its 35,000-square-foot Reserve Roastery on Chicago's Magnificent Mile.There are four floors, each with a coffee bar with slightly different offerings, as well as a roof terrace.You can get exclusive drinks and merchandise only available at its Reserve Roasteries.The world's biggest Starbucks store is spread over four floors, has a roof terrace, roasts its own coffee, serves luxury coffees and cocktails, and sells a range of exclusive merchandise that you can't find elsewhere.Starbucks' biggest store isn't in Seattle, where the coffee giant is based.