PHOTO Object 505 – Top Secret Underground Airbase Željava


There are many interesting locations near Plitvice Lakes, but one of them is not only very interesting, but also very mysterious. It is called Željava Airbase, a top-secret underground airbase located on the border of Croatia and Bosnia and Herzegovina under Plješevica Mountain.

We visited Željava this winter and took some photos that portray the current situation in this area that attracts many curious visitors!

This was the largest underground airport and military air base in the former Yugoslavia, and one of the largest in Europe.

Construction of the Željava or Bihać Air Base began in 1948 and was completed in 1968. The airport has been fully operating from 1968 until 1992, when it was destroyed during the withdrawal of the JNA by activating explosives.

The whole complex was mined and extremely damaged with more than 50 tons of explosives on May 16th 1992.

The Socialist Federal Republic of Yugoslavia invested approximately $6 billion in its construction. In the end, only ruins remained.

The main purpose of the airbase was defense and distraction of potential aggressors on the former Republic. Consequently, it has always been in the interest of foreign secret agencies. That was proven nowadays by declassifying the records of the CIA spy satellites, which have been monitoring the construction of this object from the orbit for years.

The Airbase Željava consisted of:

underground object Klek, code name Object 505
five runways
a barrack
a radar at the top of Plješevica Mountain
34 other buildings

The complex of underground tunnels and galleries was divided by 56 armored doors, and it had 4 entrances.

The dimensions and the weight of the doors were truly impressive; three doors were 60 cm thick with a width of 20 m and height of 4 m, weighing 100 tons and running on electricity, while the fourth door worked on hydraulic principle, with a thickness of 80 cm, width of 20 m and height of 9 m.

Available data suggest that the Klek facility could withstand an impact of max strength of 20 kilotons.

The Airbase Željava included several external facilities. Among them were five runways, barracks situated 3 km away from the base, garages, workshops, and other buildings. Radar station and communications center were located at the top of the Plješevica Mountain. The warehouse containing rockets and bombs was located in Vedro polje.

Now Željava is abandoned and quite a dangerous area, because there is no official information about the current situation inside of the tunnels.

Many tourists come here, but we don`t suggest that you go on your own hand, or go deep inside of tunnels because there could be dangerous animals or other unexpected situations. Good news is that Željava is finally getting more attention and we can expect some news soon regarding this very special object and area. Until then, enjoy this photos and videos!

This is how it looked in 1989:

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