Follow-up: this is the St. Peter and St. Paul church in Peterhof, Russia, outside of St. Petersburg. Designed in 1895 to resemble a classic medieval palatial church, it has only recently received a full restoration for use as a people’s cathedral. Construction was completed in 1905, but due to two world wars, a revolution, and communist suppression, it was not used as a church until 1990. At one time, it was occupied by the Wehrmacht

Today, it ranks as one of the most beautiful churches in the world. I hope to visit it someday.

https://lidenz.com/little-known-amazing-churches-sts-peter-and-paul-cathedral-in-peterhof/