The large swamp fire in Waikato's Whangamarino wetlands is now under control

The blaze has burned through more than 1024 hectares - with a 15 kilometre perimeter.

Fire and Emergency Incident Controller Mark Tinworth says its a significant milestone - and crews don't expect the fire to grow any more in size.

He says drones will be operating overnight to monitor hotspots and any flare ups.

Crews will return tomorrow, to work at fully extinguishing the fire.