The clock tower in Helsinki Central Station will ring for the first time in its history on 20 August

And what it will sound like is a mystery and a surprise

Helsinki’s Central Railway Station is one of the most prominent landmarks in the city thanks to its 50-m high clock tower capped with a green top. Its clock doesn’t produce any sounds, however, on Sunday, 20 August, for the first time in its history, the tower will produce a bell ring to honour the birth of architect Eliel Saarinen – the designer of the station.

One might wonder what device will produce the ringing sound – in fact, there will be 15 of them. Each one will be marking a decade since the birth of the famous architect.

More specifically, the event is set to take place at 3 pm and as organizers have promised, it will only be a “one-off event” never to be repeated again. Or at least, not likely to happen any time soon. So, you better set your watches if you happen to be in the Finnish capital on 20 August.

However, what the sound will be like is meant to stay a secret until the moment it is produced arrives, according to VR's project manager Jani Jääskeläinen, as quoted by Yle news agency. VR, Finland’s national railway company, is behind the initiative.

A special honour for Finland’s greatest architect

The Art Nouveau station clock tower was completed in 1919 and at the time it was the tallest building in Helsinki. The clocks, however, were fitted in 1922.

The tower façade is made of granite pieces, whereas its green top is made of wood and copper – the roof alone weighs 5 tonnes. At the top of the tower, there is a globe on winged wheels, meant to symbolize the international nature of the station.

Architect Eliel Saarinen also designed many notable buildings in Finland including the National Museum of Finland, the mansion Hvitträsk in Kirkkonummi, the Munkkiniemi Boarding House and the Lahti Town Hall, among others.