The illuminated Nippara limestone cave in Tokyo’s Okutama district leaves visitors in awe on May 4. (Reina Kitamura)

The Nippara limestone cave, made even more grand by imaginative LED lighting in various hues, is suddenly a huge hit on Instagram with visitors to the site in the Okutama district of western Tokyo.

When revamping the 800-meter walking course inside the cavern in 2014, it was decided to illuminate the interior in pink, purple, blue and green to make the main chamber even more impressive.

It takes about 40 minutes to complete one circuit.

In fiscal 2017, there were 97,000 visitors, up from about 60,000 in fiscal 2012.

As temperatures remain a constant 11 degrees or so throughout the year, the cave system is a good spot to stay cool during the sweltering summer.