Johannes Jacobus Appelman, 52, of Holland, failed to stop at a stop sign at Rakaia on May 31 and crashed into another vehicle, killing Abigail Hone, 12, her friend Ella Summerfield, 12, and Ella's mother Sally, 49.
He has since pleaded guilty to three counts of careless use of a vehicle causing death and one charge of careless use of a vehicle causing injury.
The previous night, on the Coromandel Peninsula, US tourist Cody Dickey, 23, crossed the centre line in his campervan, killing Aucklander Robyn Eilleen Derrick, a passenger in an oncoming four-wheel-drive vehicle. He was ordered to pay $5500 for emotional harm, and disqualified from driving for 18 months.
Antony Rountree, owner of Wanganui's Harvey Round Rentals, said most tourist drivers hired vehicles in main centres and drove through Wanganui, instead of hiring a vehicle in the city itself.
His rental vehicles had "keep left" stickers on the dashboards, he said, adding that one difficult area for tourist drivers to navigate was the Parapara hills north of Wanganui.
New Zealand law requires visitors to hold a valid overseas driver licence or international driving permit to drive.
The NZTA says the Government is working to reduce road crashes through its Safer Journeys strategy.
Rental car companies had also implemented safety measures such as pre-travel emails to customers, on-site safe-driving instructions, "keep left" stickers on vehicle windscreens, and showing customers a safe-driving video, the NZTA said.
Road safety director Ernst Zollner said driver fatigue after long-haul flights and unfamiliarity with roads and road conditions affected overseas and New Zealand drivers.
The NZTA was working with police, ACC, local government and the Ministry of Transport on a road safety project aimed at "visiting drivers" with the initial focus directed towards the South Island, he said.
It would look at why overseas visiting drivers experienced difficulties on New Zealand roads and how to encourage safer choices.
From April , driving video footage developed by Tourism NZ and NZTA was being screened on in-bound Air New Zealand flights from China.
Mr Zollner said crash data showed more New Zealanders were killed and injured by other New Zealanders on the roads than by overseas drivers.
"But while serious crashes involving overseas visitors and tourists are relatively rare, each one is a tragedy for all of those affected."