Massive project to build a new underground highway through the heart of the city while keeping the existing elevated Central Ahtery open during construction. Now covered by the Rose Kennedy Greenway.

It is the most expensive highway project in U.S. history - at a cost of more than $1 billion per mile. U.S. Rep. Barney Frank once said it would be cheaper to elevate the city than depress the ahtery. He also once answered the question "how do you depress the Central Artery?" by saying "Have Fred Salvucci talk to it." If you get that, you probably have more of an intimate knowledge of Dukakis-era politics than is good for you.

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