We went to the Kremlin the day before leaving Moscow – it took three tries, because the first day we were jetlagged and the consensus was that art plus jet lag equals wasted time, the second day was Thursday and they were closed, but the third day we managed it.
I’m not religious, but I really enjoy church architecture and art. (The time I was in Rome as a graduate student – well, I think I saw nearly every single church of artistic or architectural interest in the whole city, and my Italian was good enough that I could actually ask caretakers/curators/etc. questions, which was an enormous help – one guy gave me an impromtu tour of the whole building, which was terrific, along with a list of other places I should go.)
Eastern Orthodox churches (at least when not designed by Italian architects, and sometimes not even then) look distinctly different from Catholic ones. The numerous domes, for one thing. And the interiors – whoa! All the interior surfaces are covered in frescoes of bible scenes or saints, except for the altar wall, which is basically shellacked with icons: square devotional pictures of Jesus or Mary or the saints. These are organized in specific patterns – there are names for all the various rows of them, and the central one is usually related to the figure or incident to which the church is dedicated – e.g. the annunciation, or St. Ivan, etc.
The overall effect is that when you are in the the church looking up, it’s hard to get a read on the interior space of the building. This is probably the intended effect – the mild disorientation is a part of the sense imparted by all the frescos and icons that one is very small. But it’s a slightly different variety of smallness than you would get in say a medieval or early modern Catholic church, where the interior tends to be shaped and laid out a little differently. More faces on the walls and less space.
St. Basil’s in Red Square provides a similar impression in a different way. Here the interior is mostly brick but it is still heavily decorated, although in more abstract patterns rather than with frescoes of saints. (The building is unusual in its design – it’s not a typical Russian church or cathedral by far.) The interior is a warren of little chapels and passageways and steps – going through it I wished I had a map with a cross-section so I had a better idea of how the inside corresponded to the outside. This is probably a silly observation, but I think a St. Basil’s Cathedral Lego set would be the most awesome thing ever, provided it was really big.