Cheonseong-san  천성산
Including  Wonhyo-san  and  Jeongjok-san
This is a range-line of three high mountains that are on the Nakdong Jeongmaek Range-Line
(southern Taebaek Range), mostly within Yangsan City of South Gyeongsang Province
(Gyeongsang-
namdo
) and partially in Ulsan City to the east.  They are mostly part of the Gaji-san Provincial Park
(Naewon-sa Sector).  They contain the famous
Naewon-sa monastery and many smaller temples that
mostly house female monks.  
Cheonseong-san and Wohyo-san, of similar heights in a remote area, have often
had their names confused on maps.  
This all runs just SE of Chwiseo-san (Yeongchuk-san) Tongdo-sa.
Index of Sacred Sites:

Wonhyo-san   (920m, south)
Wonhyo-am
Hongryong-sa
Yeonhwa-am
Won-gak-sa


Cheonseong-san   (922m, central)
Naewon-sa Monastery
Geumgang-am
Seongbul-am
Euiseong-am
Geumbong-am
Nojeon-am
Naewon-am
Yongchu-am
Yongma-sa
Mita-am
Jeoksu-am
Pilso-am
Wonjeok-am
Hwaeom-sa
Bulgwang-sa



Jeongjuk-san   (700m, north)
Daeseong-am
Anjeong-am
Jogye-am
Sijeok-sa
Unheung-saji
Buldang-sa
Yongam-sa
Gwangcheon-sa

Nosang-san   (343m, furthest north)
Myobeob-sa
Peak of Cheonseong-san in May 2008
photo by my friend Andrew Douch on his Nakdong-Jeongmaek Trek
This north-south group of mountains,
long sacred to Korean Buddhists, seems
best-known under the name of the
highest peak
Cheonseong-san.  That
title, literally "Thousand Saints (or Sages)
Mountain", means that at least 1000
monks have reached enlightenment while
studying & meditating in its temples.
It's still a very active Buddhist area today.