A hint from a trusted and esteemed source who promised to investigate it in detail soon.
Located in a bomb shelter on Ulitsa Goncharnaya (“Pot makers street”), Metro Taganskaya.
PS. Close to the Basilica hostel/hotel on Solyanka. A long-ish walk from my apartment. Not far from the Library of Foreign Literature, which is one of the hubs of intercultural activity in Moscow.