TALLINN (Reuters Life!) - The stacks of metal cases with black knobs and dials look like something from a 1950s sci-fi movie -- in fact they were once highly secret communications equipment used by the feared Soviet secret police, the KGB.
The yellowing batches of wiring plans for transmitters and receivers alongside the dusty plastic telephones are all that is left of a once-powerful top-secret communications hub used by the KGB on the 23rd floor of the popular high rise Viru hotel in the Estonian capital of Tallinn.
Though memories are fading of life in the former Soviet Union the "Viru Hotel and the KGB" exhibition revives the heydays of the Cold War when Soviet tourism agency Intourist directed foreigners to the Viru so the intelligence services could spy on them and sensitive signals were transmitted from the Baltics to Moscow.
The hotel has opened its once-secret rooms and gathered other spy memorabilia -- left over from its days as a flagship hotel for Intourist behind the Iron Curtain and a Kremlin listening post -- for the exhibition which started this year.
"All we have here now is the room as they left it one night in 1991 when Estonia was getting close to restoring its independence," said Peep Ehasalu, spokesman for the Viru, now run by Finnish hotel chain Sokos.
Estonia was annexed by the former Soviet Union and only regained its independence in 1991. It joined the European Union and NATO in 2004 and joined the euro zone this year.
The KGB used a "radio room" on the 23rd floor to relay communications from the Soviet embassy in Helsinki, 70 km (44 miles) across the Baltic sea, and had direct links to Moscow.
There were also about 10 people working for the KGB in rooms 307 and 315. From there they tapped guest telephones, studied hotel personnel files and read the reports of the tour guides working with foreigners.
The radio room became very busy in 1975, when it was used as a hotline relay for Soviet leaders between Moscow and Helsinki during the European Security and Disarmament Conference held in the Finnish capital.
Activity increased also in 1980, when Tallinn was the venue for the yachting competition for the Olympic Games, which was hosted that year by the Soviet Union.
"In the Soviet times I was not afraid of losing my job because of my professional skills, and jobs were available for everybody and no one was sacked even if they came to work drunk," said Enn Palmets, the hotel's technical manager, who has been at the Viru since it opened.
But he said there was also a culture of fear.
"There was a threat of getting dismissed because of telling the wrong kind of stories or talking to foreigners. In fact, everybody was forced to sign a document saying that they promise not to contact foreigners."
One of the main targets for surveillance were visiting relatives of Estonians who had fled the country.
"I remember one man was fired because some Finnish marks were found in his pocket," he said.
Tiia Raudma, who visited many times from 1975 when visiting from Australia said she was never allowed to stay anywhere else.
"Everyone knew the Viru was bugged and that the KGB people sat on the second and third floors near the hard currency bar, so people would just be careful in what they said on the telephone or while in the hotel."