Kirillo-Belozersky Monastery

This is claimed to be the largest monastery in Europe and Russia, and dates back to the 14th century. One side faces out over a lake, and the grounds are surrounded by a wall. There are numerous chapels and churches. The main entrance is lined with frescos.

The monastery was de-consecrated during Soviet times, but since 1999 it has been a monastery again, with six residents. At its largest, back in the 16th century, there were over 200 monks living here.

I added this as an example of Russian construction worker conditions. 

They are apparently restoring an onion dome.