Seoul's Sadong-san   서울사동산
the Four Guardian Hills of inner-NE Seoul
part of the Bukhan-san Sub-range
Nak-san, Anam-san,  Gohwang-san  &  Baebong-san
 낙산      안암산      고황산      배봉산
When Seoul was chosen as national capital in 1390, the arrangements of the mountains
surrounding it was a key factor.  In the scheme of five "inner" mountains that should
surround the palace and walled city, three of them are obvious and prominent -- Bugak-
san to the north, Inwang-san to the West and Nam-san to the south (the slight hill where
the Westin Chosun Hotel and the Temple of Heaven now stand served for the center); the
city wall and it's great gates ran and still run along their ridges.   But there is no real
mountain on the east side of old Hanyang, only four significant hills outside of the East
Great Gate [
Dongdaemun] to serve as physical and spiritual guardians.  This was a glaring
weakness that was noted by the great geomancer-monk Muhak-daesa, who predicted that
when the capital fell the invading army would enter from the east;  this came true.
We can call these four spiritual-guardian hills Seoul's Sadong-san [4 East Mountains],
a name that fits with Korea's numeric-religious traditions.  They are found just north of and
further east from the East Great Gate [
Dongdaemun], keeping north of the Cheonggye-cheon
Stream
(that flows east out of downtown and then curves south to the Han River) and west of the
Jungrang-cheon Stream
(that runs south from Uijeongbu, collecting the waters of the northern parts of the
Bukhan-san sub-range, until it merges with Cheonggye-cheon)
.  Their areas were forested and rural
during the Joseon Dynasty, but are completely urban neighborhoods of Seoul today.
The Sadong-san is composed of Nak-sa, Anam-san, Gohwang-san & Baebong-san.

Nak-san  
(70m)

Anam-san (90m) is the home of Korea University (one of Korea's top-10), and hosts the significant
traditional Buddhist temples Gaeun-sa and Bomun-sa.  Nearby it to the SE is the Seonnong-dan,
the site where kings from the Unified Shilla, Goryeo and Joseon Dynasties held ceremonies
intended to coax good harvests from the earth, during which the king himself would plow the field
in front of the altar.  This is now famous as being the site where
Seolleong-tang was invented
during one of these ceremonies, by Royal order -- this is the popular soup with calcium-rich broth
made by boiling cattle bones for a long time, than adding strips of beef and noodles.  Rice and
small slices of green onion are added at the table.  

Gaeun-sa [Awakening-Transfer Temple] was founded in 1396 by the great geomancer-monk
Muhak-daesa, under the initial name Yeongdo-sa, as part of his design for reconstruction of
Hanyang as the new capital for Joseon.  It is found partway up Mt. Anam's southern slope, right
next to the large campus of Korea University.  It was not particularly illustrious in the early days.  
In 1779 the tomb of a favored concubine of King Jeongjong was constructed next to it, giving it
higher status.  it is written that when the prince who became King Kojong was a young boy in the
mid-1800s, he spent a few years here for his education.  In 1921, a new abbot reconstructed the
buildings and built a bell-tower, and it became an education/study- center for the national Jogye
Order, as it remains today.  Gaeun-sa's Main Hall enshrines a Buddha statue from the end of the
Goryeo Dynasty made of cloth covering a frame that was then covered with many layers of
lacquer -- unusual.  Its Three Spirits Hall is entitled a Chilseong-gak on its signboard, following
the common pre-20th-century tradition.
Gohwang-san (150m) is the home of KyungHee [Gyeonghui] University (another of Korea's top-10),
giving it a famously beautiful campus; and flanking that, the Hanguk University of Foreign Studies

(HUFS,
Weidae) and the Korea Advanced Institute of Science and Technology (KAIST).
It also hosts two medium-size urban Buddhist temples, Gwanbul-sa
(headquarters of the Gwanbul
Sect, in Imun-2-dong)
and Yeonhwa-sa of the Jogye Order (right behind the KyungHee University Hospital).
Baebong-san (105m) is a public city Park to the southeast of the other two.  
It doesn't host any temples or shrines that I know of.
Gohwang-san with KyungHee University