Zeljava a secret military base in BiH

[Cmok]

The airbase Zeljava has to been one of the most interesting secret objects in ex Yugoslavia. Construction on Objekt 505 Klek (the codename of the airbase) began in 1956 and after 12 years it was completed in 1968. The cost was enormous, 7-8 billion dollars (approximately 50 billion dollars today). Located in the valley of mountain Pljesevica its strategic position was excellent. The whole base was built in in the inside of the mountain Pljesevica. A radar was positioned on top of the mountain, and it's said that it could track all flights in an area from Budapest to Rome, meanwhile Pljesevica provided superb cover from radars trying to detect lift offs from the base. It was designed to accommodate 50 MiG 21 planes, 150 service men and could withstand a direct nuclear hit. In an event of all out nuclear war the base could completely seal up, blocking all radiation from penetrating and could sustain itself for a prolonged period of time (it was equipped with supplies of food, water and gas and could generate electricity and clean air independent of outside sources and conditions)

Marsal Tito visiting the base

The base was a government secret and naturally taking photos/videos was strictly forbidden. Although there was propaganda material featuring Zeljava released every now and then to show the might of the Yugoslav Peoples Army. Luckily for us there were soldiers and officers who served there that didn't abide the rule and gave us an opportunity to see what it looked like when it was operational. A video that surfaced after the war shows some parts of the inside of Zeljava.
MiGs parked on the runway

 

[Cmok]

Unfortunately during the Yugoslav wars the base was a military goal for both Serbs, Croats and Bosniaks. The still active Yugoslav Peoples Army command decided that the base was too valuable to fall into the hands of anyone and on 18th of May 1992 the base and the runway were rigged with more than 50 tons of explosives which were activated at 5:30 in the morning. To ensure maximum destruction prior to detonation the base was sealed up, as in a case of nuclear attack. Huge pressure generated from activating the explosives caused the base to explode from the inside out.
Today Zeljava is lying in ruins. Due to enormous amount of damage it's completely unusable, and serves only as a tourist attraction for local military enthusiasts. Part of the underground base is still explorable, however it should be noted that there are some serious risks. Huge cement blocks hang from the walls and could collapse at any moment, also there's a risk of radioactive exposure from destroyed smoke detectors within the base.

Concrete doors used to seal the base completely:

A Douglas C-47B Dakota still stands outside the base, although in very bad condition:

Location on GoogleMap: Google karte

I'd be glad to answer any questions regarding the base and post more photos if anybody's interested.