is a history of two versions of the San Francisco—Oakland Bay Bridge: the original bridge built in 1936 and a replacement for the eastern half of the bridge finished in 2013. The 1936 bridge revolutionized transportation in the Bay Area and profoundly influenced settlement patterns in the region. It was also a remarkable feat of engineering. In the 1950s the American Society of Civil Engineers adopted a list of the “Seven Engineering Wonders” of the United States. The 1936 structure was the only bridge on the list, besting even the more famous Golden Gate Bridge. One of its greatest achievements was that it was built on time (in less than three years) and came in under budget. Mikesell explores in fascinating detail how the bridge was designed by a collection of the best-known engineers in the country as well as the heroic story of its construction by largely unskilled laborers from California, joined by highly skilled steel workers. By contrast, the East Span replacement, which was planned between 1989 and 1998, and built between 1998 and 2013, fell victim to cost overruns in the billions of dollars, was a decade behind schedule, and suffered from structural problems that has made it a perpetual maintenance nightmare.This is narrative history in its purest form. Mikesell excels at explaining highly technical engineering issues in language that can be understood and appreciated by general readers. Here is the story of two very important bridges, which provides a fair but uncompromising analysis of why one bridge succeeded and the other did not.