In the 1800s there used to be horse racing along what is now called Commonwealth Ave, but eventually there was too much traffic, so Frederick Law Olmsted's company was hired to design a race track for horses (and sulkies) and bicycles along the river in Allston. It ran from where the Arsenal St bridge is now (where Western Ave ends) to where the the Eliot bridge now is.
I would not be surprised if there actually were the occasional ostrich race back then. But it looks like it was mostly used for horses.
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