TONY JONES, PRESENTER: It's the oldest community in the world's most rapidly ageing society. Nestled in the mountains of central Japan, Nanmoku Village could be the future for many societies around the globe. Some parts of the district haven't seen a baby born for more than a decade. The ABC's north Asia correspondent Mark Willacy reports.

MARK WILLACY, REPORTER: It's time for the maths lesson in the Year Two class at Nanmoku Primary. And for the school's only Year Two student, Yuska Awi (phonetic spelling), that means no dodging work or grabbing a nap.

"As the only child in Year Two, I feel really lonely," he tells me.

Once there were 1,200 primary school students in Nanmoku Village. Now, there are just 38.

KAZUO KASHIWAGI, PRINCIPAL, NANMOKU PRIMARY (voiceover translation): With the number of students dwindling, I wonder if there'll be anyone left soon. If the school closes, it means the heart of the village will be gone, so it's a lonely feeling.

MARK WILLACY: It looks picture postcard perfect, but Nanmoku could be a glimpse into Japan's dark future.

Once a community with a thriving silk and timber industry, it's now full of abandoned and decaying homes, their owners either dead or departed to the big cities.

There are more than 7.5 million empty houses and apartments in Japan. That's about 10 per cent of all residences in the country. And here, in this district of Nanmoku, more than two-thirds of homes have been abandoned.

Tamako Mitsugis and her husband Kazuo have popped next door to give their neighbour's home a good airing. Its last resident, old Mrs Asakawa, died 16 years ago. And inside, it seems as if time itself has stood still. The Mitsugis are the only people left in this part of the village. Everyone else has either died or left. So they keep an eye on the abandoned homes, ensuring unwanted intruders are kept out.

KAZUO MITSUGI, NANMOKU RESIDENT (voiceover translation): Until recently we were quite negligent about locking the doors, but recently a big monkey broke into the nearby shop and stole some hair dye.

MARK WILLACY: While vainglorious monkeys run riot, there is a distinct absence of another more vital demographic.

TAMAKO MITSUGI, NANMOKU RESIDENT (voiceover translation): I can't remember the last time a child was born in this part of the village. The youngest child here is now in Grade Five. So it must be about 11 years ago that the last baby was born here.

MARK WILLACY: Out of its population of nearly 2,500, there are just 10 babies here. In fact there are so few children, Nanmoku's baseball team has been disbanded. The only sport played in the village is gateball, a mallet game similar to croquet.

While there are 10 babies in this village, there are also 10 people over the age of 100. 106-year-old Masu Koido is the oldest of the lot. So I popped in to Nanmoku's nursing home to ask her why the people of this village live so long.

MASU KOIDO, NANMOKU RESIDENT (voiceover translation): Well, I would wake early in the morning and go for a walk. Our farm grew vegetables and that's what I ate. I would pick it and eat fresh food. I was told I could live for a very long time.

MARK WILLACY: While there's been no specific research into why Nanmoku's residents seem to live so long, others have their own theories. Doctor Ayum Ohsawa comes to the village twice a week to check up on the locals.

AYUM OHSAWA, DOCTOR (voiceover translation): The people here live together with nature and they accept that death is part of nature. So it's not just the clean air and water, but it's also the fact they're very healthy mentally.

MARK WILLACY: But it's clear Nanmoku will not survive unless there's some sort of regeneration, so the mayor is doing all he can to attract young people to the village.

NUBUO ICHIKAWA, NANMOKU MAYOR (voiceover translation): We offer people free kindergarten and free school lunches. We give people transportation money and other cash incentives when they move to the village. Last year, 13 people, including three children, moved here.

MARK WILLACY: But none of these new kids was in Year Two, meaning Yuska Awahi (phonetic spelling) still has to handle his maths classes on his own. It's this scene that really sums up fate of Nanmoku, a future some residents are slowly beginning to accept.

TAMAKO MITSUGI (voiceover translation): In a word, it's lonely here. One person dies and then another. Eventually, in 20 to 30 years, the village will simply dissolve.