High atop Changbai Mountain, Tianchi shimmers like a sapphire-blue jewel, but only for a limited time each year

Want to test your luck? Then head to Changbai Mountain in Northeast China's Jilin province.

At the top, you'll find Tianchi, also known as Heaven Lake, which was formed over 1,000 years ago when a massive volcanic eruption created a vast crater that was gradually filled by rainwater and underground springs.

Here's where the luck comes in: There is a saying that "you don't choose to see Tianchi — Tianchi chooses to show itself to you".

At an altitude of 2,189 meters, Tianchi has different scenery across four seasons, but it's said that visitors can only see its fully clear, sapphire-blue view for roughly 50 days a year.

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It stays frozen for seven months starting in December, with wind whipping snow particles across the volcanic crater.

During the early thaw season, clear ice and sapphire-blue water gradually emerge — a rare, breathtaking sight before ice fully melts in summer, which is Changbai Mountain's peak tourist season.

The weather there changes rapidly, though, and access to Tianchi will be closed during strong winds, fog, rain and snow, or when roads are icy.

Now, Tianchi's frozen surface shines pure and bright, like stunning jade embedded atop the towering peaks of Changbai Mountain.

"It's worth traveling all the way to Changbai Mountain. Tianchi is such a special natural wonder, and it's a once-in-a-lifetime chance to see it in person," said Shanghai-based blogger Adam James McIlmoyle from the United Kingdom, who has about 179,000 followers on social media platform Sina Weibo.

Visitors can take the shuttle bus to Tianchi from the north slope and enjoy many scenic spots. The west slope offers amazing panoramic views of Tianchi, but reaching them requires climbing more than 1,400 steps.

Like many tourists, McIlmoyle chose the north slope for its easy access, hopping on a shuttle bus at the tourist center and transferring to a van halfway up the mountain.

Magnificent mountain and forest views gradually reveal themselves on the journey upward.

Tianchi is not the mountain's only attraction. If the way to the lake is closed due to bad weather, there are other sights for visitors to see.

Nearby is the 68-meter-high Changbai Waterfall. It looks totally different depending on the season: a rushing waterfall in summer and a stunning wall of ice in winter.

Visitors will also see locals in clothes featuring a classic floral pattern popular in Northeast China selling eggs that have been boiled in natural hot spring water.

McIlmoyle hiked through a snowy valley and lush forest, walked beneath tall trees, and sometimes followed streams along the path. He could hear the soft creak of trees in the wind and the gentle sound of flowing water.

"It's such a magical adventure," he said.

He soaked in an open-air, 40 C pool at a hotel of Julong Hot Springs. Surrounded by snow, the warm water soothed and relaxed his body.

Another viral activity is rafting along the river, especially in winter, when snow and rime adorn both banks.

The breathtaking natural scenery of the Changbai Mountain region is attracting a greater number of inbound tourists, thanks to China's visa-free entry policy.

"The visa-free policy allows me to book flights and freely travel to China at any time. Immigration clearance is also very convenient. We were extremely lucky to see the pristine Tianchi, fulfilling my parents' long-cherished wish," said Oh Na-hyun, 41, who traveled with her elderly parents from South Korea.

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Tour guide Xu Wanling from the Yanbian Far East International Tourism Co in Jilin said that she mainly guides elderly Russian tourists. "They love taking photos of Tianchi from different angles and sharing them with me excitedly," she said.

From March 31 to April 30, Changbai Mountain offers free admission to all visitors at its north and west slopes.

"The policy has attracted more domestic tourists and international visitors, including those from South Korea, the United States and Russia. To offer a diverse travel experience, we promote the in-depth integration of tourism with sports, culture and healthcare, such as cycling in summer and skiing in winter," said Li Yuxin, an official from the Changbai Mountain management committee.

Contact the writers at xulin@chinadaily.com.cn