You'll probably see Metropolitan Cathedral across town before you actually find this amazing place of worship. Look around inside if the doors are open or just appreciate the facade from the street.
This Old City principal church is an interesting spot to kick off your day of sightseeing. There's lots to explore nearby, including Piata Uniri, Romanian Orthodox Cathedral, and Dan Paltinisanu Stadium. Take your time at Metropolitan Cathedral before heading to these other fine sights.