... I think 666 is an address that a lot of cities probably avoid. Best I could tell, there is no building that has that address, but if the finish line had its own address, it would be 666 Boylston.
Unless the physical location of the finish line has been moved, the decision to put it in that exact location, rather than 30 feet to one side or the other, had to be made a long time ago.
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