The so-called "Seven Sisters" are seven buildings which became the first Soviet skyscrapers in the time of Stalin. For a long period of time they remained the highest buildings in Europe. Initially they planned to build eight of them, they even made a stylobate in Zaryadye, but finally they constructed the "Rossiya" hotel on it. Today, there are seven "skyscrapers of Stalin": Moscow State
University on the Vorobyovy Hills, Ministry of Foreign Affairs, two residential ones, and two hotels - "Ukraine" (Radisson Royal) and "Leningrad" (Hilton Leningradskaya). Stars are only on six of them because the spire of the building accommodating the Ministry of Foreign Affairs was too fragile to hold a star. They are all different and made from different materials.