The largest NZ Defence Force exercise in 15 years is underway in the Bay.
Exercise Alam Halfa will involve about 1500 people from the NZ Defence Force, bringing together maritime, land and airmobile forces.
Troops will practise in a high-end combat setting, while the scenario requires them to restore peace and transfer control of a fictional country back to law enforcement and democratic authorities.
"These exercises form a vital part of the NZ Army's operational cycle," NZ Brigade Commander Colonel Chris Parsons said.
"They allow us to prepare for a variety of likely contingencies - to ensure that New Zealand can play its part in our region or around the globe reducing conflict and improving stability."