Lenin’s mausoleum in Moscow’s Red Square offers up one of Moscow’s most macabre attractions and perhaps the most famous “modern mummy” in the world.
Frozen in time, Vladimir Ilych Lenin’s embalmed body lays within a red granite and black labratorite step-pyramid. Here visitors may gaze on it in the dark, cool of the tomb. The sarcophagus is kept at a constant temperature of 16° C (61° F) and humidity of 80 - 90 percent. Weekly, a mild bleach is used to fight discoloring fungus and mold on Lenin’s skin, and every eighteen months the corpse undergoes a chemical bath of glycerol and potassium for thirty days while the mausoleum is closed. During this time, Lenin’s clothes are washed and carefully ironed. And every three years, Lenin receives a new suit.
Lenin can be viewed for five minutes at a time in small groups under the watchful eye of guards in every corner of the room.
https://www.atlasobscura.com/places/lenins-mausoleum