A cave built in the 1960s
The cave was built for the needs of the Postal and Telecommunications Administration and the Defense Forces. Construction began in the early 1960s and, according to drawings and equipment completion dates, was completed in 1968–1969. Equipment installations began in 1969 in equipment facilities managed by the then Finnish Post and Telecommunications Board. The cave, with its EMP protection, represented the state-of-the-art technology of its time.
When the cave was built, all telephone traffic was hand-held and testing and installation of the first transmission equipment had just begun in Finland. Data traffic was still at the level of Morse code, telegraph was a tough thing, and telex equipment made its entry. Telex was a major data transmission medium until the end of the 1970s, after which the era of faxing began.
The Cold War and mysterious stories
The post-war period and the perspectives of that time are easily forgotten when looking at the cave today. The world and Finland were then faced with very different challenges and at the beginning of a technological revolution. The structures and equipment of the cave were designed and built for the needs of the Cold War. They responded to the supposed threats of the era and ensured the defense of the area. Tele-side task was to ensure the functionality of telephony and respond to its development.
The cave was built and equipped on the quiet, and its true purpose has been carefully guarded. Only a few locals have been aware of the construction of the cave. There were attempts to conceal its existence, especially because of its significant role in the defense forces. The secrecy of the early times has caused a stir of various rumors and conjectures around the cave. Various imaginative stories have been heard to this day.
From the point of view of the Defense Forces, the location of the cave has been based on the location of Satakunta’s Air Command and airport. The cave has been excavated at the highest point of the ridge, with good views of the sea, the airport and the surrounding areas.
For the Defense Forces, the cave has played an important role as strategies vary according to the needs of the time. The equipment of the Defense Forces was dismantled from the cave in the spring of 2009, when the sale of the cave became topical. There have also been some military exercises in the area where the cave has been occupied.
Link station in the best location
For the Finnish Post and Telecom Agency, the highest place in the area was best suited as a link station and an excellent mast placement, given the future leaps in technology towards links. The Finnish Post and Telecom Agency invested its latest technology in the equipment facilities and masts of the cave. The use of the station as a link station culminated in 1980–1998, when transmission technology evolved from the early 1970s to the mid-1990s. At that time, link technology evolved and was the only technology that could economically realize the growth of telephone traffic in the post-automation period. Coaxial cable routes passed through the cave, and terminals for coaxial systems were also present in the cave. However, their capacity did not reach the level of links.
The station served as the home of the first mobile networks when they entered the market. Initially, a fully manual ARP network was used, which was later automated to semi-automated. This was followed by the NMT 450 and NMT 900, as well as the first Mobile Phones, the most significant of which was Nokia’s “stick”, which is also familiar from many films. The previous devices were, by the current standard, mostly drag-and-drop models, and many were car-only. At their most expensive, they cost up to FIM 50,000 (over 8,000 €).
Significant transit point for fiber connections
The digitalization that began in the 1980s led to the development of the fiber-optic cable network. The first commercial fiber and system equipment in Finland and Tele came between Haistila Cave and Rauma. The speed of the system was 140Mbit and it was numbered 140V001. The next-generation system was also introduced in the same range with the identifier 565V001, which quadrupled capacity. The devices were manufactured by the French company Alcatel.
Next, the fiber was built all the way to Pori and a little later via Nakkila, Harjavalta and Kokemäki to Tampere. The cave became a transit point for significant fiber connections, through Rauma all the way to Sweden. Fiber cables became more common in the 1990s and thereafter at an ever-accelerating pace, with links no longer needed in the backbone network. They were decommissioned by 2009, so the cave also became unnecessary for Sonera.
The circle closed when the cave returned to its original purpose
Since 2009, the cave has been owned by Luolakallio Oy, whose founders’ brothers Erkki and Hannu Kallio offered event activities in the cave during the years 2009-2019. At the end of 2019, four domestic IT companies acquired Luolakallio Oy’s share capital and the cave for the provision of computer room services, i.e. for the purpose for which it was built during the Cold War.