Russian Railways has introduced a special offer for travel on double-decker train #103/104 between Moscow and Kislovodsk. A ticket for a compartment (upper berth) costs 1,999 rubles, according to Travel.ru.
The ticket sales period is still unknown, but travel is possible until April 16. The promotion can also be used for shorter routes on this route—for example, Moscow to Rostov-on-Don, Pyatigorsk to Voronezh, Ryazan to Rostov, Moscow to Tikhoretsk, and so on. In these cases, tickets should be purchased for the full Moscow to Kislovodsk route and used only for that portion.
Source: travel.ru