Middle Bass Island is an island of the U.S. state of Ohio, located in Lake Erie. A small town, Middle Bass, lies on the island. The 805-acre (3.258 km²) island is shaped like the Big Dipper and is one of three Bass Islands located at the center of a group of 23 smaller islands.
Some of its more famous neighbors are South Bass Island, with the town of Put-in-Bay, Kelleys Island, and Pelee Island. The island has a year-round population of 95 residents (2000 census). Seasonal population surges to near 1,500 residents during the summer.
The island was landed upon by French explorer, Robert La Salle, in 1679. The abundance of wildflowers on the island impressed La Salle and his crew so much that they appropriately named it Isle des Fleures, the Floral Island. It would retain this name for the next 200 years until it was acquired by a German count in 1856. With the aid of immigrant German workers, the island was used for growing grapes. This proved to be a very successful undertaking.
By 1875, Middle Bass Island's Golden Eagle Winery was reputed to be the largest wine producer in the United States. The Lonz family acquired the business in 1884 and owned and operated it until the death of George Lonz in 1968. Lonz Winery has often been compared with the wineries of the German Rhineland. The old castle-like structure has been visited by countless dignitaries including five American Presidents. The winery is now part of a corporation bearing the Lonz name. Since 1979, the wines have been made by Italian enologist Claudio Salvador.
Lonz Winery was purchased by the state of Ohio with the intention of one day establishing a state park.