No, an UFO didn't land in Helsinki. That round structure is not an UFO, is not a bomb shelter, it is a church. It may be one of the attractions of the city but I'm a "the older the better" kind of person and all modern architecture don't attract me.
FI-778971, sent by Outi.
Temppeliaukio Church is a Lutheran church in the Töölö neighborhood of Helsinki. The church was designed by architects and brothers Timo and Tuomo Suomalainen and opened in 1969. Built directly into solid rock, it is also known as the Church of the Rock and Rock Church.
FI-116615, sent by Britta.
Plans for the Temppeliaukio/Tempelplatsen (Temple square) began as early as the 1930s when a plot of land was selected for the building and a competition for the design was held. The plan by J. S. Siren, the winner of the second competition to design the architecture of the church, was interrupted in its early stages when World War II began in 1939. After the war, there was another architectural competition, subsequently won by Timo Suomalainen and Tuomo Suomalainen in 1961. Construction finally began in February 1968, and the rock-temple was completed for consecration in September 1969.
Photo by Kaarlo Valkonen
FI-1650793, sent by Eero.
The interior was excavated and built directly out of solid rock and is bathed in natural light which enters through the skylight surrounding the center copper dome. The church is used frequently as a concert venue due to its excellent acoustics. The acoustic quality is created by the rough, virtually unworked rock surfaces.
The Temppeliaukio church is one of the most popular tourist attractions in the city; half a million people visit it annually. - in: https://en.wikipedia.org/wiki/Temppeliaukio_Church