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With a history of work stoppages that runs up to the current day, SEPTA has been called the most-strike prone transit agency in the nation. But the biggest transportation strike in Philly happened before it was created — and spread far beyond its streetcar origins.

It was 1910 when the Philadelphia Rapid Transit Company fired a couple hundred staffers for the simple offense of unionizing.

Thousands walked off their jobs running the streetcars, and the movement spread, breaking out into protests that sometimes turned violent. When state police were brought in, organized labor launched a general strike that saw more than 75,000 participants in Philly and spread to Newark, San Francisco, and New York.

Scroll down to read the thread on how things unfolded that late winter into spring.