Deep beneath our feet lies a secret. The Rock Center of Little Gellért Hill. It is a mostly subterranean military complex. This place is shrouded in mystery. It’s time to explore its hidden history.
The Rock Center is also known as Sziklaközpont. It’s under Little Gellért Hill. This hill is the western part of the well-known Gellért Hill. The complex has another codename. It’s called Deep 23. The Rock Center once housed the National Counter-Air Center. Don’t confuse it with the Citadella. The Citadella has a military bunker too. It’s called the Gellért Hill bunker.
Currently, Hungary’s military intelligence agency controls the premises. It’s the Military National Security Service. Although declassified, it remains closed. The general public and press cannot enter.
Construction began in the interwar period. It finished during World War II. The Rock Center served as a military depot. This was due to wartime necessity. During the siege of Budapest, the complex was sealed off.
After the war, it became the National Counter-Air Center. It was established on October 1, 1948. Technical installation was complete by September 1949. The Rock Center functioned as the host until 1957. It was the central command hub. This included air-based counter-air defense. It also included ground-based anti-aircraft artillery. Plus, it coordinated air raid defense activity.
From 1965 to 1999, the Rock Center hosted Hungary’s air traffic Area Control Center. This was according to an agreement. The parties were the Hungarian People’s Army. Also the government and the state-owned airline MALÉV. The ACC used paper-based control until 1981. Then radar control was officially introduced. Controllers sometimes had to use VFR. This required maintaining self-separation.
From 1965 to 1970, air traffic controllers worked inside the bunker system. In 1970, they moved to the RISZ building. This was a multi-story building connected to the bunker. In early 1975, they moved back to the Rock Center. In late 1980, radar systems were installed. These were on the roof and fourth floor of the RISZ. In January 1981, controllers were assigned to the third floor. They worked there until 2000. Then the ACC moved to Budapest Ferihegy International Airport.
For a time, the complex also housed Magyar Telekom’s fax center. Until recently, the Rock Center was top secret. Some parts were abandoned in 1944. This was during Allied bombings. Other areas were sealed off during reconstruction. The original size is unknown. It was built in a former underground quarry.
The Rock Center is under Little Gellért Hill. The complex includes an underground bunker system. There is also at least one building above ground. It is a four-story building called RISZ. The main entrance is on Schweidel Street.
The bunker system occupies parts of a former quarry. The quarry is surrounded by dolomite. The entrance is sealed with a thick blast door. Rumors say the bunker connects to other bunkers. These are on Gellért Hill and Eagle Hill.
The RISZ building originally had three stories. MALÉV added a fourth floor. RISZ is an acronym. But its meaning is not publicly known. The Rock Center remains a fascinating enigma. It is a testament to Budapest’s complex history. It is a secret world beneath our feet.