Spring clean for Helsinki’s Soviet-era nuclear bunkers
Helsinki is well placed should a nuclear attack materialise, with fully functioning underground shelters that are not only secure but also seek to offer some normality for those forced to seek refuge.
Neighbour Russia at war, Finland’s bid for Nato membership and fear of mass destruction have led citizens in the Finnish capital to “declutter” their bomb shelters in preparation for what may follow.
Finland has, since 1945, built enough bunkers to shelter 4.4 million people – just one million shy of its total population.
“People have not been paying attention to our shelters for decades, using them as storage, but the Ukraine war made them think about preparedness for themselves and their families,” said Petri Parviainen, Helsinki’s civil defence unit chief.
He is speaking 20 metres below the Earth’s surface, in a cavernous room carved out of Finland’s 1.8 billion-year-old bedrock and painted white.
He is standing in front of a thick metal door designed to withstand the blast from a nuclear bomb. Behind that is another set of doors that seal off the underground caverns from radiation and chemical agents.
Situated in a down-at-heel part of Helsinki and 150 kilometres from the Russian border, the Merihaka bunker is entered by a square glass structure in a paved square. It contains a lift alongside five levels of broad steel stairs.
In an emergency, the bunker can be filled to its capacity of 6,000 in an estimated 20 minutes. A further 10 minutes are required for civil defence volunteers to seal the doors.
Inside, there is enough water for three weeks, but no food.
The bunker network is part of Finland’s comprehensive defence planning, which includes many thousands of troops and the largest artillery stock in Europe.
It also relies on military intelligence that, it is hoped, would give its people 72 hours’ notice of hostilities and warning of an imminent attack.
At that point, the 40 sirens stationed in Helsinki would sound, signalling to its 650,000 residents, along with tens of thousands of tourists and commuters, to take cover in shelters that have space for 900,000.
“If we are under a general warning, people will receive information via sirens or their 112 app to move to the closest shelter,” says Tomi Rask, of the civil defence unit.
“When the personnel are in the shelter, the doors are closed and the shelter is over-pressurised against any hazardous materials.”
Several safety features can be used, depending on the threat.
“Individual shelters are given notice when to go to radiation-filtering mode. It takes 10 to 15 minutes to close the shelter and go on to full sheltering mode,” he says.
Mr Rask points to an access road that allows cars to park in one of the caverns, the curves of which dissipate blast pressure, while its double doors “keep out toxic chemicals and gas-related weapons attack”. He taps the wall reassuringly.
“This shelter is really good against nuclear attack and chemical weapons, and the bedrock can take a lot of radiation.”
The Merihaka shelter currently houses a children’s soft play area – possibly the world’s safest – a cafe, and three hockey pitches alongside the car park.
It also has bunk beds for 2,000 sleepers to use in eighthour shifts, toilets and washing facilities. Citizens are expected to bring their own food, medicine and sleeping bags.
For decades, most Finns ignored the monthly siren tests that sound on the first Monday of every month. But on the three most recent occasions, more attention has been paid to the shrill sound.