I visited St Isaac’s cathedral.
Apparently this is the fourth largest Church in Europe, in terms of volume under the dome, after St Peter’s in Rome, St Paul’s in London and the Duomo in Florence.
It is also a subject of controversy at the moment, because it has been managed as a museum (I think by the government of St Petersburg), since the revolution, but this month they have decided to hand it to the Russian Orthodox Church at no cost.
This is not quite as simple as it sounds. After the fall of communism, St Isaac’s has still been a museum, and Church services are only conducted in one of the side chapels. You have to pay about $5 to visit it, but the Orthodox Church says it will not charge anything, even though part of it will still be treated as a museum. Some people fear it will no longer be maintained well.
Anyway, the view from the dome is extensive,
The paintings and mosaics are spectacular and beautiful
And the technical details of how they made it are interesting