Witness the "ice monsters" — one of Yamagata Prefecture's natural wonders — in a special illuminated event this winter beginning on Dec. 28 at the Zao ropeway in Zao.

The '"monsters" are actually trees covered in coatings of ice, which are known as juhyo in Japanese, and they can only be seen in certain parts of the mountainous regions of the country. The formation of a juhyo requires a combination of strong winds, low temperatures and snowfall on evergreen conifer trees. Since they develop differently depending on the weather conditions and the shape of each tree, no two juhyo are alike.

At the lit event, visitors can ride the ropeway to view the panorama of juhyo from above.

The illuminated event should leave participants "lost in a world of fantasy," organizers say. Dress warmly, as this ice-monster phenomenon only occurs during the coldest months of the year (usually between December and March), so it won't just be the extraordinary view that will give you the chills.

Yamagata's ice monsters are lit up at Zao Onsen in Yamagata from Dec. 28 through March 2, between 5 p.m. and 9 p.m. Fee for the ropeway is ¥2,500 (¥1,250 for children). For more details, call 023-694-9518, or visit www.zaoropeway.co.jp.