Konstantine City is a city on Helghan.
Konstantine City was first mentioned in Scolar Visari's message to Helghast troops at the end of Killzone: Liberation. It was also implied in the same message that the Helghast might have secured a second nuclear weapon (Red Dust) and stored it there.
In Killzone 2's interlude messages between chapters, Visari evacuated the civilian population of Pyrrhus to Konstantine City and mining villages during the ISA invasion of Helghan in Operation Archangel. ISA Intelligence believes that approximately 5 million people lived in the city regular but 20 years after Helghan was devastated the city now only has 125,000. The headquarters of Thoralf-Sigurd-Vig was also located in Konstantine City.
- Intel from Killzone: Mercenary reveals that the Helghast fleet that appeared at the end of Killzone 2 were stationed in Konstantine City.
- Konstantine City was most likely named after the Byzantine Emperor, Constantine I, or even Constantinople, the Byzantine's Empire's capital city. This would make sense as this would imply that Konstantine City has impregnable defenses.