RIGA (Reuters) - Pitch-black corridors, the stink of damp and peeling walls give the impression of a medieval dungeon: the Russian writing on heavy metal doors hints at the building's true purpose.
This was the basement of the "House on the Corner," the headquarters of the KGB secret police in Latvia.
The building, a satellite of the notorious Lyubyanka in Moscow, is soon to be vacated by the Latvian state police and some are campaigning for it to become a place of remembrance for those who suffered during 50 years of Soviet occupation.
Former Soviet dissident Janis Rozkalns remembers being brought from his detention cell on the first floor to the basement, now full of old furniture and chunks of rusting metal.
"We walked past cells like this, the showers were at the end of the corridor where in the days of Stalin people were shot," he said, standing in a disused detention chamber.
"I can only envisage that there should be a memorial museum here. I am very unhappy that this place is in a complete mess, history has been partly destroyed here," said Rozkalns, who was arrested in 1983 for anti-Soviet agitation and sent to a Siberian prison camp.
The KGB's predecessor moved in 1940 after dictator Josef Stalin forcibly incorporated Latvia into the Soviet Union.
Then began what Latvians call "the year of terror" when there were mass deportations to Siberia and shootings in the basement of the House on the Corner.
Interrogations were on the sixth floor of the building, on the corner of what used to be Lenin Street and Engels Street.
Those who want it turned into a museum say authorities must ensure the building, built in 1912, is not sold to a developer for commercial use. It originally housed flats and shops, before being taken over by the pre-war Latvian Interior Ministry.
Any museum would complement the Occupation Museum, which shows the crimes committed when Latvia was invaded and occupied first by the Soviet Union in 1940, then Nazi Germany from 1941-1944 and again by the Soviets in 1944 to 1991.
Modern Russia still refuses to talk about occupation and says Latvia joined the Soviet Union voluntarily.
Richards Petersons, historian at the Occupation Museum, said much research was still needed on what actually happened at the House on the Corner, when and how many people suffered.
Its bloodiest period was believed to be in the first year of Soviet rule and in the early stages of the Soviets' return.
"I think it has enormous historical significance. This place is unique in Latvia, there is no other building like it," he said. "Other museums of this kind are very impressive."
The KGB museum in Latvia's Baltic neighbor, Lithuania, is an important shrine to suffering and a tourist attraction.
Hungary's capital Budapest has "Terror House" in the former secret police headquarters which is devoted to the twin terrors of fascism and communism, though with more emphasis on the latter.
Rozkalns said visiting the basement again reminded him how his life felt at an end when his cell door slammed shut.
Though the execution of prisoners was a thing of the past when he was arrested, the building still inspired fear, he said.
"If someone got a call saying 'come to the House on the Corner' ... it was clear the absolute worst could happen to him, his family, his kids and his relatives," said Rozkalns who left behind two 3-month-old children when he was sent to Siberia.
Rozkalns was released from the prison camp in 1987, stripped of his Soviet citizenship and deported to Germany. He returned to Latvia after it regained its independence in 1991.
The basement is the only part of the building accessible to visitors before the police move out finally at the end of March.
Peep holes in the doors of a row of cells and in the wall show how the guards kept an eye on their prisoners.
In one cell is a noticeboard with documents in Russian detailing various administrative routines. Huge metal doors marked with "shelter" in Russian open off the corridors.
In one basement room old furniture is piled up. Lying on top is a plastic plaque of the founder of the Soviet secret police, Felix Dzerzhinsky.
In another cell is a pile of old boxes, some filled with used bullet shells. A police official is quick to say the bullets were not those used to kill prisoners during Stalin's rule.
Helena Celmina, a detainee in the 1960s, recalls in her memoirs a bitter joke about the House on the Corner.
What is the tallest building in Riga?
The answer was The House on the Corner, because from its sixth floor you could see Siberia.
Reporting by Patrick Lannin; Editing by Robert Woodward