OC Transpo was founded in 1972 by merging several municipal transportation systems. The organization introduced the Transitway bus rapid transit system in 1983, pioneering BRT in North America. In 2001, OC Transpo launched its first light rail service, the O-Train Trillium Line. The system underwent major expansion with the opening of the Confederation Line in 2019, marking Ottawa's transition to a modern light rail network. This transformation represents one of the largest infrastructure projects in the city's history.