ArchBoston alerts us to the centennial of the opening of the "Cambridge Subway" from Harvard Square to Park Street.

Some Red Line history.

On the morning of the opening, the Globe reported the subway cost $11.75 million, and added:

There will no doubt be a heavy patronage today, as many who would not otherwise have reason to patronize the new "tube" will enjoy "seeing it," or, actuated by a desire to recall years hence with pride that they "rode through the first day," will join the regular travelers between Boston and the University City.

Also noteworthy, according to another Globe account: The Boston Elevated Railway Co., as you might expect from its name, had the right to build an elevated from Harvard Square to Boston, but bowed to protests from Cambridge residents and burrowed underground.

Photos from the BPL's Boston Elevated collection. Posted under this Creative Commons license.