Mum Jo Rollo, of Kamo, said her children were playing on the water slide where she expected them to be for some time: "My kids are enjoying all the free stuff, especially the sausage sizzle."
Tana Manuel, of Kaitaia, said she and daughter Payton Karena, 1, were having a great day. It was the first time they had attended and were happily collecting lots of giveaway material.
Yesterday was the first day of autumn but did not feel like it, with the temperature peaking at about 26C.
Manaia Primary Health Organisation's Hannah Mitchell, who helped organise the event, said they usually attracted 1200-1500 but this year seemed busier.
"It's just a day for families to come together," she said. "It's like a gift."
Free buses were travelling to the event from Kamo, Otangarei, Maunu, Tikipunga and Onerahi. Children's Day had been running in Whangarei for about 15 years.
Sharon Davis of community organisation Te Ora Hou said she had been helping out for what felt like "a thousand years" but still enjoyed it.
"I just love it," she said. "We're celebrating children hard-out."
