What is the land region of Russia that has largest cities and most people?

The land region of Russia that has the largest cities and most people is the European Plain. The European Plain, also known as the Great Russian Plain, is a vast lowland area that stretches from the Ural Mountains in the east to the Baltic Sea in the west, and from the Barents Sea in the north to the Black Sea in the south. The European Plain is home to some of Russia's largest cities, including Moscow, St. Petersburg, and Nizhny Novgorod, and is also the most densely populated region of the country.