As Japanese prepare to head for the hills Thursday for the nation’s inaugural Mountain Day holiday, retailers and tour operators are gearing up for an  ¥820 billion windfall.

They're counting on customers like schoolteacher Ayako Kobayashi. The 33-year-old spent more than $700 on a sleeping bag, mattress, backpack and trekking food to climb Mount Kita near Nagano last weekend. She's looking to buy a two-person tent and a bigger backpack next, which would set her back another $1,000. The high price tag is worth it, she said.

"I can't find words to describe the feeling of achievement that I get at the top of the mountain," Kobayashi said. "It makes me more confident."