Thousands have turned out for Anzac Day dawn services commemorating the anniversary of the 1915 Gallipoli landings.

Undeterred by rain, thousands have gathered at the cenotaph in Auckland Domain for the country's biggest dawn service.

The Auckland War Memorial Museum and the Sky Tower were lit up in red for the occasion.

Hats, jackets and umbrellas were the order of the day and many attendees huddled under the eaves of the museum.

There was applause from the crowd as the veterans marched out of the museum onto the forecourt.

In offering prayers, Royal New Zealand Navy Chaplin Colin Mason made special mention of those who have lost loved ones most recently while serving in Afghanistan.

Anzac Day is the 98th anniversary of the landings, where a disastrous campaign cost the lives of 2721 of the 8556 New Zealanders who landed at Anzac Cove.

Turkey lost 87,000 men during the Gallipoli campaign - double the number of allied forces.

Rain was forecast for many places around the country with the national commemoration service taking place at the National War Memorial in Wellington at 10.30am.

Defence personnel will provide a dawn to dusk vigil over the Tomb of the Unknown Warrior at the memorial.

Tinui, the tiny Wairarapa town that hosted New Zealand's first Anzac Day service in 1916, was also holding a ceremony, while 84 veterans are in New Caledonia to mark the 70th anniversary of New Zealand's involvement in the War in the Pacific.

At Gallipoli, Defence Minister Jonathan Coleman and head of the air force Air Vice-Marshal Peter Stockwell will represent New Zealand.

Anzac Day services will also be held where defence force personnel are stationed overseas.