The hall of hotel "Polesie" was filmed in the Palace of Culture and Sports. Here, Valery Legasov who led the commission that investigated the Chernobyl catastrophe drinks vodka in the bar. The cloakroom desk played the role of the bar counter. 

The scene in which Boris Shcherbina selected volunteers to climb under the reactor was filmed in the same building, on the first floor.

The interiors of “Polesie” hotel rooms were filmed at another place, also in Vilnius - see our next stop (https://reveal.world/story/1969)