Sacred Daoist Mountain of China
Qīngchéng-shān [青城山, Azure Castle Mountain; Cheongseong-san in
Korean], located in Dujiangyan City
(north of the huge Chengdu City) in Sichuan
Province, right on the far-eastern edge of the Tibetan Plateau, became
a UNESCO World Heritage Site in the year 2000.  
official page here.
This name should not be confused with the Qinling-shan mountains, also sacred to Daoism.

"The temples of Mount Qingcheng are closely associated with the foundation of Taoism, one of
the most influential religions of East Asia over a long period of history.  The functions, religious
traditions and the special religious status of [its] Taoist temple cluster are fully preserved while
still maintaining traditional building styles.  Furthermore, internationally accepted protection
guidelines and rules have been adhered in conservation and repair projects in terms of location,
design, materials, and techniques."

"Mount Qingcheng dominates the Chengdu plains.  There are eleven temples on Mount Qing-
cheng of special significance in the field of Taoist architecture because, unlike Mount Wudang
temples, they do not reproduce the features of imperial courts but the traditional architecture of
western Sichuan.  The Erwang Temple west of Dujiangyan City was considerably enlarged
during the Song Dynasty (960-1279) and substantially reconstructed in the 17th century.  It is
constructed of wood and is located on a commanding point of the mountain, overlooking the river.
The carvings inside the temple record the history and achievements of water control.

"In 142 CE the philosopher Zhang Dao-Ling founded the doctrine of [his school of] Taoism on
Mt. Qingcheng, and in the following year he took up permanent residence in what became known
as the Celestial Cave of the Tianshi (the name given to the spiritual head of the Taoist religion).

"During the Jin dynasty (265-420) a number of Taoist temples were built on the mountain, and it
became the centre from which the teachings of Taoism were disseminated widely throughout
China.  During the Tang Dynasty the works of Du Guang-ting, one of the most important figures
in Chinese thought and science, were collected together there as what came to be known as the
"Taoist Scriptures."   The troubled period at the end of the Ming Dynasty and the beginning of
the Qing Dynasty, in the 17th century, saw Taoist scholars and disciples converging on Qing-
cheng from all over China.  Thereafter the sacred mountain resumed its role as the intellectual
and spiritual centre of Taoism, which it has retained to the present day."
"青城山" by Charlie Fong - his own work.  Licensed under Public Domain via Wikimedia Commons
Wikimedia Commons page on Qingcheng-shan with several photos
"Fuhan" Zhang Dao-ling  [輔漢 張道陵, sometimes just known as Zhang/Chang Ling;  he is Bohan Jang Do-
in Korean] is said to have lived from 34-156 CE during the Eastern Han Dynasty, dying in his
physical human form at 122 years old and becoming an "immortal" [
shinseon in Korean], ascending
to Heaven in a spiritual form in front of his disciples.   His scholar-name "Fuhan" can be translated
as "Good-Fortune of the Chinese People" or "Assist the Han Dynasty".

Daoists say that he was originally fron Jiangsu Province, and that he was inspired by reading the
Daode-jing  道德經 as a student in the Taixue Imperial Academy.  After graduation he served as a
magistrate in what is now Chongqing City.   Desiring a life of spiritual practice, he retired very early
and led a reclusive life at Beimang-shan [near Zhengzhou City of Henan Province],  where he
practiced the attainment of longevity.   When the emperor heard of his reputation and thrice invited
him to serve as a professor in the Taixue, he thrice refused by claiming that he was ill.
He was led to meditate as a holy-hermit in a
cave on Heming-shan [Crane-cry Mountain],
in Dayi County on the west side of Chengdu
City, Sichuan Province,  by its outstanding
Qi  [氣, ch'i, vital energies; gi in Korean].  
It is said that when he attained supreme
enlightenment the spirit of
Laozi appeared
to him and transmitted higher teachings on
how to "banish the superficial & flowery,
and return to the simple & true."  

Laozi then conferred the religious title
"Celestial Master of the Three Heavens"
upon him, the name he is venerated as in
Daoist temples all over China -- a.k.a.
"Ancestral Celestial Master Zhengyi Zhenren"
[祖天師 正一真人].    He is often depicted in
paintings and statues as riding on a tiger,
in the manner of Buddhist Bodhisattvas.
He then moved further northwest to Qingcheng-shan, again due to its powerful qi and again focusing
on meditation (with perhaps by now some disciples) in a mid-slope cave
(now incorporated as one of the
temples there)
.  They say that upon emerging from his cave-retreat he began to heal thousands of sick
people, by combining ancient shamanic / herbalist folklore with Daoist understanding of qi.  He taught
disciples who flocked there due to his reputation, and is regarded as the founder of the Celestial
Masters Way [
天師道, Tiānshī-dào; Cheonsa-do in Korean] sect, which became a mainstream school
of Daoism.

An important commentary on the
Daode-jing named Xiang-er [想爾, Reflections; Sang-i in Korean] is
traditionally ascribed to Zhang Daoling's authorship, but is now thought more likely written by his
grandson Zhang Lu, the third Celestial Master;  anyway it reflects his teachings and remains a basic
text of Tiānshī-dào thought.  Only the first half of the sole extant sixth-century manuscript was found
a Dunhuang cave)
, however.  Like the Daode-jing itself, the Xiang-er advises both individual practitioners
and rulers of societies.  It teaches adepts on pathways to attainment of immortality -- by internal-
alchemical meditation techniques, the internal-spirits formed by interactions of qi (organ-spirits or
"chakras", can be understood as patterns of organic behavior) can be nourished -- just like ancestral
and natural spirits are nourished and become benevolent by the performance of offertory rituals.  The
text discourages employment of "external" techniques such as exercise-yogas and sexual practices.  
It instructs political elites to remake their nations according to Laozi's Dao, reducing all desire for
wealth, fame, distraction and luxury, but allowing natural morality to blossom from the healthy roots
of respect for and harmony with the changes of Heaven and Earth.

Zhang Dao-ling started a theocratic government-system of Daoist parishes in southwest Sichuan
Province, which promised 240,000 adherents salvation from an immanent religious apocalypse, and
its price of cult-membership led to his school also being known as the "Five Pecks of Rice Way"
五斗米道; Wǔ Dǒu Mǐ Dào].   This was the first known group of Daoists that could be considered to
be an organized religion, even a rebel-nation, and its leadership became hereditary.   The apocalyptic
doctrines mostly disappeared from Celestial Masters Daoism by the Tang Dynasty, but by then
political troubles during China's many civil and northern wars from 200 through the late 500s had
resulted in the scattering of the teachers and dividing of doctrines.  

The school persisted for the remainder of Chinese history, focused mainly on ceremonies for deities
such as the Celestial Masters and Perfect Ones, but became overshadowed by the
[全眞道, All Truth or Complete Perfection; Jeonjin-do in Korean] School during and after the Song
Dynasty.   The known heir-masters of Celestial Masters Daoism fled to Taiwan in 1949 to escape
the communists, and teach modernized doctrines and lifestyles there today.

There is now reported to be a revival of Tiānshī-dào teaching and practices at the surviving temples of
Qingcheng-shan, said to remain an extremely beautiful mountain that attracts many tourists as well as
pilgrims -- but the lineage of those masters and the authenticity of their doctrines remain unknown to us.