The film was shot in a record five days.
After filming for five days straight for almost 15 to 18 hours a day, most of the cast and crew didn't speak to each other after the wrap up as they were all thinking about how Soldiers suffer in real life.
Even in the packed schedule of 5 days the crew had to suffer delay because of sudden rains which halted filming for almost 4 hours during the 4th day.
Bunker is the first Indian film to show the mental trauma of a soldier.
The One location film was shot in a 12 by 8 feet bunker.