Russia is enormous, and getting around requires some thought. The good news is that domestic transport works well, even if distances are vast.
Air
Domestic flights are the only practical option for crossing Siberia quickly. Aeroflot remains the largest carrier, with a comprehensive network out of Moscow. S7 Airlines, Ural Airlines, and Pobeda (a low-cost carrier) also serve many routes. Book in advance for better prices, and be aware that schedules can change at short notice.
Rail
Trains are the backbone of Russian long-distance travel and a genuine pleasure. The network is extensive, comfortable, and affordable. Overnight trains between Moscow and St. Petersburg take around eight hours in a sleeper compartment -- a civilized way to travel. The Trans-Siberian Railway from Moscow to Vladivostok takes about six days and crosses eight time zones.
Russian trains run in several classes. First class (SV) offers two-berth compartments, second class (kupe) has four-berth compartments, and third class (platskart) is open-plan with bunks. All long-distance trains run on Moscow time regardless of local time zones, though suburban trains use local time. Buy tickets at the station, through the Russian Railways website (rzd.ru), or via booking apps.
Metro
Moscow and St. Petersburg both have excellent metro systems -- fast, cheap, and architecturally spectacular. Moscow's metro stations are famous for their chandeliers, mosaics, and marble halls. Several other cities including Kazan, Novosibirsk, and Yekaterinburg also have metro systems.
Bus and Marshrutka
Buses and marshrutki (minibuses) serve shorter routes and smaller towns. They are cheap but can be slow and crowded. For getting between towns not well served by rail, they are often the only option.
Car
Driving in Russia is possible but challenging. Roads outside major cities can be rough, distances are enormous, and signage is mostly in Cyrillic. In cities, traffic congestion is severe, particularly in Moscow.
River
River cruises between Moscow and St. Petersburg via the Volga and connected waterways are a popular way to see the countryside. Services also run along the Volga to cities like Yaroslavl, Nizhny Novgorod, and Volgograd.