Tourists visiting the area are often directed to Shooting Butts Rd at the eastern end of Dublin St where there is the Rapaki Hillside Walk.
South Wairarapa Mayor Adrienne Staples said the situation was a tragedy.
"We're extremely upset that something like this should happen in our district.
"I wouldn't want anybody to have this happen to them, but to be a visitor, and a visitor on their honeymoon, it makes it even worse."
A spokeswoman from the United States Embassy said they had contacted the family and were working closely with them on arrangements "during this difficult time".
"But for privacy reasons we are not able to share any more details."
The man's wrecked rental vehicle was discovered nose-first in a ditch on Shooting Butts Rd just after 7am by a passing member of the public.
It is unclear what time the crash happened.
A 2km stretch of the road was cordoned off until mid-morning while the Serious Crash Unit examined the scene.
The cause of the crash is still being determined and the man's name will not be made public until his family have been notified.
The man's wife is being supported by Victim Support in Wellington.
A woman who lives in a property close to the crash scene said the gravel road was dangerous and narrow.
Emergency services were called when a passing motorist discovered the Jucy rentals Toyota Estima just after 7am.
Wairarapa Police Area Commander Donna Howard said the man was visiting New Zealand with his wife.
Howard said the crash involved just one vehicle and the man was dead when emergency services arrived. His wife was not with him.
At the crash site there were paint dots marking the tyre tracks of the rental which appears to have veered to the right, up onto a grass berm and crashed into the drain culvert, about half way along the road.
The owner of a Shooting Butts Rd property, near the crash scene, said her husband had got up at about 3am to make a cup of tea.
"When he came back to bed he said 'what's that funny noise - is it rain?'," said the woman, who did not want to be named.
"Now I'm thinking perhaps it was the horn of the vehicle going."
The woman said she could see fire crews from her house.
Her teenage granddaughter said she and her grandfather went to check on the sheep and saw the crashed vehicle up close.
"It was nose down, it had fallen into a ditch and it was pointing straight up."
The woman said the rural road was dangerous and narrow.
"It's really only a one-way road. There's pot holes and a twist in it, and at the edge of it they have dug a channel for drainage.
"When there's long grass there of course you can't see it. We know it's there but anybody not familiar with it wouldn't.
"It's very sad," she said.
South Wairarapa District Council infrastructure and services manager Mark Allingham said the road was commonly used by locals as a shortcut to Martinborough from Tuturumuri.
This was the first crash on the road that he was aware of.
"The speed limit is 100kmh but that's not really suitable," he said.
"People try and drive on dirt roads the same as they would on a sealed road but they need to drive to the conditions."