Tower caisson for the Mackinac Bridge (40 of 45)

Working to the south tower caisson.  This is ring 16.  Almost to bedrock (7), Electronic reproduction of photograph.  The Mackinac Bridge 1954 - 1958. Mackinac Bridge Authority
Abstract/Description: Working to the south tower caisson. This is ring 16. Almost to bedrock (7)
Subject(s): Bridges--Design and construction
St. Ignace (Mich.)
Mackinaw City (Mich.)
Mackinac Bridge (Mich.)
Date Created: 1955 (approximate)