Ardern made the first of the day's announcements at low decile Te Kura o Ōtangarei School in Whangārei.
"I'm delighted to be back in Northland with so many of my colleagues today to announce initiatives that will enhance Northland's economy, create jobs and promote healthy communities," she said.
Much of the investment had been guided by the Tai Tokerau Northland Regional Economic Action Plan, Ardern said.
''The region is on the right track, but there is still more work to be done and this Government will continue to work hard and form genuine partnerships to further support Northland's growth.
"I'm proud of what we're able to announce today for Northland and the partnerships that will contribute to a great future for rangitahi and everyone here."
The Prime Minister was visibly impressed with the kura pupils' te reo rendition of Hallelujah, the much-covered song written by Leonard Cohen.
Ardern thanked the children for their "beautiful" waiata, but she wasn't the only one impressed.
''I know when it's a good song because I get kicked like crazy, and I really got kicked during that one,'' she said, indicating her late-stage pregnancy.
The song of praise was timely, as the Northland package included $8.7m to build state housing in Ōtangārei.
The Government would collaborate with community group Ōtangarei Papakāinga Ltd on a four unit housing project to provide transitional accommodation, and would fund more state housing in Kaikohe and Kaitāia.
The Ōtangarei Papakāinga funding was in response to a practical, community based desire to care for its people, Twyford and Mahuta said.
The scheme's chief executive, Martin Kaipo, said ''wellness starts in the home''.
"Safe secure housing is the priority,'' he said. ''However, we believe it is simply not enough to provide somewhere to live; whānau in urgent need of social housing tend to require a range of support in a number of areas."
The Government would also collaborate with He Korowai Trust in Kaitāia to assist low-income whānau into owning homes, and would build state houses in Kaikohe.
At a later announcement at Forum North, the Government's ''love letter'' revealed $6.25m for transport business case studies, including the unique marriage of the Twin Coast road route and tourism initiatives.
''We expect this will lead to $94m for road improvements in the region,'' Twyford said.
A separate $500,000 has been tagged for a business case study into ''renovating'' the Auckland/Northland rail corridor, and a rail link to Northport at Marsden Point.
That study would also inform the case for the main upper North Island port to be based in Whangārei Harbour, Winston Peters said.
Further announcements in Kaikohe and Kerikeri yesterday included forestry partnerships with Northland iwi.
Hot on the heels of this week's launch of a $6m tree planting partnership with Ngāti Hine Forestry Trust, Shane Jones announced Te Uru Rākau (Forestry New Zealand) would work with Ngāti Rēhia to establish a commercial forest on the hapu's land.
The PGF would also invest $288,000 to explore the establishment of a kauri sanctuary – free from kauri dieback – on about 45 hectares of sheltered Ngāti Rehia land, Jones said.
Also in the Northland package:
■ $4.4m in He Poutama Rangatahi partnerships to help youth into employment or training, ''to help the region change its story" (Employment Minister Willie Jackson).
■ $6.6m to Project Crimson Trust's Trees That Count campaign over three years, for planting native trees nationwide, part of the One Billion Trees scheme (Forestry Minister Shane Jones).
■ $6.9m new funding for the Hundertwasser Art Centre and Wairua Maori Art Museum, added to an already pledged $3m.
