Well, that didn't take long. On the fourth day in service, a bus on the Purple Route of the Charm City Circulator was sidelined on Calvert Street near Redwood Street about 9:15 a.m. this morning after what appears to have been a collision with a passenger vehicle. Police were at the scene.

Cathy Chopper, a spokeswoman for the Baltimore Department of Transportation, confirmed that there had been a collision there  this morning but said there was no damage to the bus  and minor damage to the car. She said there have been several minor accidents on the Orange Route, which started up in June, but nothing previous on the Purple.

It looks like Baltimore drivers might need a refresher course in how to interact with buses on the streets. Rule No. 1: A bus in the curb lane won't necessarily stay in the curb lane.