Nabegataki Falls

Nabegataki is about ten metres high and twenty wide, which is modest, but the rock behind it has been undercut - the soft layer eroded faster than the hard cap - leaving a shallow cave the full width of the fall. A path runs into it, so you can stand dry behind the sheet and look out through the falling water at the gorge. The undercut is a legacy of the enormous Aso caldera eruption around ninety thousand years ago, which laid down the pyroclastic rock the stream is still cutting through. It is small, it takes an hour, and it is genuinely worth the drive because the view from behind a waterfall is uncommon. Morning light comes through the sheet best. The site is on private-managed land with a fee and set opening hours, and it closes when the water is high.

What you actually see

• A walk-behind fall - a path into the undercut hollow the full width of the sheet.
• Looking out through water - the gorge seen from the dry side of the fall.
• Aso pyroclastic rock - the undercut a legacy of an eruption ninety thousand years ago.
• Morning light - coming through the sheet best in the early hours.

When to go

April to November; mornings for the light. An hour.

Honest expectations

There is no practical public transport - a car is required. The site closes in high water and has set hours. It is small, and the visit is short for the drive. The path behind is wet and slippery.

Nearby

Kurokawa Onsen is south; Mount Aso is south-west.