as i see, you guys saw the article and think that Russia is still URSS...
Calm Down and Relax, cause is not true... Nobody can STOP you of visit Norilsk or NijniyTagil or any other places in Russia, if you have at least $10.000 to spend, you are good to go... Yes, you need a lot of money, cause Air Tickets in RUSSIA are fucking expensive, for ex: i can fly from New York to LA from $99 to $1000, usually around $250-$350, thats about 3500 miles = up to 6000km. in RUssia for the same distance you have to pay double, triple and even quattro. So, from Moscow to Norilsk Air ticket can be from $1200 to $2000/$3000, to make a difference: from Moscow to New York you can get very easy a ticket for $800-$900, but if you buy with time reserve, 1-2 months, then you can buy same ticket for under $500

But for Russian local destinations, this is impossible...
Now about Norilsk, the city is not Closed, the city is full of Coruptioners and Mafia rules there, the main problem there is Corupt Gov. and broken infrastructure... Norilsk is a Gold Mine for Russia, but nobody can control and Stop Mafia...thats why you'll never see there people driving expensive cars, living in expensive houses and so on... People like Hadarkovski, Abramovich and a few others, make money in cities like Norilsk, but they dont live in Russia, they live in UK/USA/EU and they invest all their money in other countries but make those money in Russia...