Visitors review the oath of the Communist Party of China at the Baota Mountain in Yan'an, northwest China's Shaanxi Province, April 25, 2019. (Xinhua/Liu Xiao)

BEIJING, Sept. 19 (Xinhua) -- Chinese President Xi Jinping has called for carrying out in-depth study of the Yan'an spirit and vigorously promoting and carrying forward the spirit.

Xi, also general secretary of the Communist Party of China (CPC) Central Committee and chairman of the Central Military Commission, made the remarks in a letter to congratulate the China Yan'an Spirit Research Society on the opening of its sixth congress in Beijing on Saturday and on its 30th founding anniversary.

Xi extended greetings to all comrades who have been dedicated to promoting the Yan'an spirit.

Yan'an, in northwest China, was once the base for the CPC during the 1930s-40s, before the Party won the revolution and founded the People's Republic of China in 1949.

Calling Yan'an a shrine for China's revolution, Xi said the Yan'an spirit fostered by revolutionaries and communists of the older generation during the years in Yan'an has become an invaluable source of inspiration for the Party.

Xi called on the members of the society to uphold the correct political direction and serve the overall work of the Party and the state in a new historical context and endeavor to offer a strong impetus to completing the building of a moderately prosperous society in all respects and to embarking on a new journey to fully build a modern socialist country.

Founded in May 1990, the society is dedicated to studying and promoting the Yan'an spirit and has made contributions in this regard over the past 30 years. ■