Can`t believe no one has mentioned:
1. THE RUSSIAN ARK ( Russkiy kovcheg ) 2002
2000 cast members, 3 orchestras, 33 rooms, 300 years, ALL IN ONE TAKE !
or
2. Kontroll ( 2003 Hungary )
The massive labyrinthine netherworld that is the Budapest subway system provides the stunning setting for ‘Kontroll,’ where ghost trains and ghostly characters, are what run through the perpetual night of this fictitious underground (metro) system.
You would probably like Konchalkovksy’s “Siberiade”