Sun Link says 3 million passengers have ridden the streetcar in its first three years and change of service.
The streetcar, which operates between downtown and the University of Arizona, started in July 2014.
"We’ve made big strides over the first three years, and we look forward to becoming an even stronger part of our community," said Steve Bethel, Sun Link General Manager, in a statement.
For more information on the streetcar, including a social media contest it's running to commemorate the anniversary and rider milestone, click here.
