BEIJING, July 1 -- President Xi Jinpinghas called on members of the Communist Party of China (CPC) to maintain loyalty and devotion to the Party and the people, on the 94th anniversary of CPC's founding.

Xi made the remarks on Wednesday in a letter to six members with the No.1 land survey team of the National Administration of Surveying, Mapping and Geoinformation.

Founded in 1954 when the country was in dire need of survey data for national defense and economic development, the team has paid nearly 100 visits to uninhabited areas of Tibet, Inner Mongolia and Xinjiang.

Their tracks covered more than 57 million kilometers -- enough to go around the Earth 1,400 times.

This year is the 40th anniversary of China's first independent survey of Mount Qomolangma. The six senior team staff, all CPC members, were involved in the survey.

"Forty years ago, your team bravely entered the forbidden zone and overcame hardships to complete our first calculation of the mountain's height, along with military survey personnel and mountaineers. The Party and the people haven't forgotten your meritorious services," Xi wrote.

The team's major work included mapping islands and reef as well as the reconstruction after the 2008 earthquake. They were once awarded the title of "Heroic Survey Team With Eminent Achievement and Selfless Dedication" by the State Council, China's cabinet.

Xi noted that generations of surveyors had endured difficulties and made sacrifices to measure the beauty of the country, making prominent contributions to the country's development.

Xi praised the team for their patriotic spirit and achievements, urging all CPC members to love and contribute to the Party while maintaining ties with the people.

"The Party cause and the people's cause rely on the loyalty and devotion of millions of Party members. Keeping to our original aspirations will lead us to ultimate success," Xi said, quoting a Chinese proverb.

Among the team's numerous stories, one dates back to 1960 when members were stranded in a desert of Xinjiang. Wu Zhaopu volunteered to stay behind to look after data and equipment while giving the last of his food and water to those who set off to find help.

Three days later, teammates returned from a water source 200 kilometers away, only to find Wu's dried up body and his mouth filled with sand. His toothpaste and ink were all eaten up, and the equipment was protected by his clothes from the sand, with all data papers arranged in order.

Sixteen years later, when Wu's son Wu Yong'an followed in the father's footsteps and joined the No.1 land survey team, his first mission was to the same desert. Failing to find his father's grave, Wu sprinkled water on every unnamed grave along the way, had a good cry, and continued survey.

Over the 61 years, the team has lost a total of 46 members to drowning, road accidents, hunger, frost and lightening strikes, among other disasters and incidents.

"It's not that we're obsessed with pain or rough living. The nature of our work demands that we are not afraid of sacrifice, otherwise, we couldn't do our jobs," Liu Jian, Party secretary of the team, told Xinhua.

"We can only gain a foothold in the survey field with hardworking spirit and devotion," Liu said.