That bottle, cast for the Minneapolis Coke bottling works in 1948 and filled at the Winona Coca-Cola Bottling Co., was the last 6.5-ounce glass returnable bottle of Coca-Cola filled and capped in the United States.
This beloved and iconic Coke bottle was the product of a 1915 design competition won by the Root Glass Company of Terra Haute Indiana. This design was unique and produced a practical bottle shape that could be instantly identified, even in pitch darkness, solely by feel.
So distinctive was the design it was both patented and trademarked. And so successful that for the next 40 years – until 1955 – the only way you could buy a Coca-Cola was in the 6.5-ounce returnable bottle or in a glass as a fountain drink. In 1955, King-sized Coke was introduced, in returnable 10, 12, and 26 ounce Family Size bottles. Coke in cans was introduced in 1960.
Here is more background from the Winona Daily News.