Chuiseo-san
Yeongchuk-san
Tongdo-sa
통도사
The Grand Monastery of Buddha
Geumgang Gyedan  Diamond Precepts-Altar Monument
a.k.a. the Tongdo-sa Bulsari-tap
Main Hall
The 17 Hermitages of Tongdo-sa:

Seo-un-am

Biro-am's  Chilseong-do
Assemblies of monks in Korea's largest temple pay honor to
Great
Vinaya Master Jajang-yulsa, founder of Tongdo-sa and
designer / builder / establisher of the Geumgang-dan Altar.
another Shilla pagoda, in front of the Yeongsan-jeon Hall
The Geumgang Gyedan  [금강계단, 金剛戒壇, Diamond/Vajra Precepts Platform] is Korea's primary
historic
gyedan [戒壇, ordination-altar], and the holy centerpiece of Tongdo-sa.   It is designated
as National Treasure #290 along with the
beopdang (法堂, Main Dharma Hall) facing it.   It is a
square granite platform with a second raised square level in the center, upon which rests a bell-
shaped
budo [浮屠, reliquary stupa] standing on a double lotus-flower-motif base; there is a stone
fence around it all with an arched stone gate (and a modern-built outer stone fence around that);
all parts are decorated with Buddhist motifs.  

The budo contains
sari  [舍利, sarira, crystal post-cremation relics] and other personal relics of
Sakyamuni the Historical Buddha (563-483 BCE) said to have been brought over the Silk Road
and obtained at China’s Wutai-shan (五台山);  and therefore this is considered to be one of the
Jeokmyeol-bogung  [寂滅寶宮, Silent Nirvana Treasure Palace] sites, and Tongdo-sa is the
“Buddha Temple” in Korea’s unique
Sambo Sachal  [三寶寺刹, Temples of the Three Treasures
of Buddha, Dharma, and Sangha] system.

Novices become monks of the Jogye Order by standing at this altar and vowing to maintain the
monastic precepts and seek enlightenment, in periodic group ceremonies called
gujokgye  [具足戒,
the complete set of precepts].   After the return of Master Jajang (慈藏) from Tang Dynasty China to
the Silla Kingdom in the mid-7th century he was named Supreme Buddhist Overseer (antecedent
to the title
Guksa) and empowered to establish Tongdo-sa in 646, centered around this ordination-
altar which became the first official one in Korea.   It is still regularly used for
gujokgye ceremonies.