Photos: The Symantec bunker

The Symantec bunker was built by the UK government in the early 1990s to shelter key utilities workers in the event of a nuclear attack and was originally a reservoir. The entrance is set into a hill near Winchester.

For our full feature on Symantec's bunker, click here. 

The glassed-off room that is the Security Operations Centre. Workstations are constantly manned by up to 15 analysts. Threats are also monitored on the four flatscreens on the facing wall.

Symantec collects information from their customers' intrustion prevention and detections systems and their firewalls. This data is analysed, and customers are told if they are under attack.

Malicious code can be dealt with in the bunker, or it can be escalated to Symantec's security response centre in Dublin. Symantec's global infrastructure is in constant communication, and includes labs in Calgary, Dublin and Auckland.

All workers must sign in and out at this terminal when entering and leaving the bunker. All visitors must be announced at least 24 hours beforehand, and this extends to Symantec employees without the necessary security clearance.

The view out of the bunker towards the airlock, with door-locks on the left. The doors can be closed, and the air inside filtered in the event of the external atmosphere becoming toxic.

For our full feature on Symantec's bunker, click here.

Want to see one of the UK's other leading security firms at work? Click here to see our photos of the inside of Sophos' Pentagon.