I mostly found the mix of architecture in Moscow to be fascinating. I would see "pre-revolution" buildings with Pagoda's on the roof right next to modern hotels. My own preference is for the historical buildings,but seeing the old mixed with the new gives perspective.
One thing struck me as really odd,though. One of the downtown Moscow McDonalds sits across the street from a nuclear reactor. Seriously. I can't even begin to guess the casualty numbers if it were to ever meltdown,or guess the number of local resident living close that were born with birth defects and died early.
One one of my trips there I visited a city in Soviet "Indian land" that was there primarily to build Soviet nuclear rockets. It was originally a small town in a remote region populated almost entirely by "Russian Indians". Yes,"Indians". As far as anyone knows they were the original people inhabiting what is now called "The Mari Republic",and were pretty much the only people there until Stalin started forcing Slavs and everyone else from all over the USSR to move into cities so he could both control them,and to industrialize the USSR in the 20's and 30's,and really kicking into high gear during WW-2. You can go to the museum there and see photos taken in the 20's that show dark people with braided hair wearing buckskins,moccasins,feathers in their hair,and living in teepees and traveling the rivers in birch-bark canoes.
Then Stalin forced them and the Slavs into sharing buildings in the same Soviet apartment complexes,and boys and girls did what boys and girls tend to do,and the Mari have now virtually ceased to exist as a unique people. In fact,it is normal to see more local citizens that look like Mongols than it is to see Mari if you go there and walk around.
Anyhow,I guess things went ok for the people there until the mid-1950's. People who had never had electricity or running water,were now living in what seemed to be palaces now,with electricity,tv's, running water,hot water,central heating,refrigerators,modern ovens,flush toilets,and showers. They also had steady jobs in local factories close to where they lived,and buses to ride to work. They no doubt thought they were taking dumps in tall cotton.
Then the 50's hit,the Soviets learned how to build nukes thanks to American and British commies that were traitors,and the Mari Republic was far enough away from Moscow or any other "important city" the Soviet authorities thought it would be a good place to manufacture Soviet nuclear warheads and missiles.
I have never been anywhere in my life where there were more deformed and crippled children and adults. What made it worse was they were all living in these tall Soviet-era apartment buildings,and most didn't have elevators that worked,or were safe enough the residents were willing to take a chance on riding in them. This is really hard on the elderly people who ended up being the ones taking care of the children with birth defects that couldn't walk.
The US got together with the USSR in a missile treaty some time in the 70's and as a part of the agreement all the nukes were removed from the Mari Republic,and the factories were supposedly cleaned up to the point there is no longer any radiation danger,but you can't unring a bell. The children I saw there then are now adults in their 40's and older,and no doubt they are still living in those tall apartment buildings. I am guessing any children they may have created are also having health,mobility,and mental issues. I have no idea if the Russian government of today that is in MUCH better financial condition than when communism collapsed have done any infrastructure repairs,or what industries may have replaced the rocket industry. Tourism and hunting seemed to be a big attraction when I was there.