The Cathedral of Saints Constantine and Helen is Baltsi's principal Orthodox church, a large domed structure in the city's southern district. Built in the early 20th century when Baltsi was part of the Russian Empire, it survived the Soviet period despite the region's heavy industrialisation and has been active since. The interior has the characteristic iconostasis, frescoes, and candlelit atmosphere of Orthodox churches throughout Moldova.
It is a working church rather than a tourist sight, but visitors are welcome outside of services. Modest dress is expected.