Before the MBTA, before even Charlie got stuck on the MTA, there was the Boston Elevated Railway Co., the El, a private company formed out of streetcar, bus and, yes, underground subways in the Boston area.
The Boston Public Library has a collection of some of their advertising posters, which both advertised the places you could go on the El and the zippy modern trains and buses it ran.
One of the sites was the South Boston Aquarium, one of a series of Boston aquariums that started with the Boston Aquarial Gardens on Bromfield Street (which PT Barnum bought and then closed) and ended with today's New England Aquarium on Boston Harbor. Thanks to a bequest from George Parkman, the city built an aquarium in Marine Park, near the Farragut statue, in 1912, according to Jerry Ryan's the Forgotten Aquariums of Boston. Its funding kept getting cut during the Depression and World War II and Mayor Hynes ordered it closed in 1954. Today, the site is home to the Murphy skating rink.
The Franklin Park poster highlights the bear dens at the Franklin Park Zoo, which were one of the zoo's first exhibits when it opened in 1912, but which were closed in the late 1950s, a couple years before the entire zoo was shut. The zoo was later re-opened, and today the city is looking at preserving what's left of the bear dens, not for bears, though, but as part of Franklin Park.
The El itself disappeared as a company in 1947, when the state took it over and renamed it the Metropolitan Transit Authority - which itself was later reborn as the MBTA. Today, you can still see some glimmers of its past by looking down for B.E.Ry manhole covers (there's a string of them from the old B.E.Ry substation in Roslindale Square up Washington Street towards Forest Hills).
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