WAT KO KAEO (วัดเกาะแก้ว)
Wat Ko Kaeo or the "Monastery of the Crystal Island" is an active temple
located off the city island in the eastern area in Kramang sub-district.  The monastery is
situated on the east bank of the
Pa Sak River on an island formed by Khlong Khao San
in the north and
Khlong Khanom Tan in the south, and confluence at the mouth
of
Khlong Dusit. The temple can be reached by taking the road (No 3477), south of the
Pridi Banomyong Bridge and parallel with the railway. North of the temple is
Wat Kluei
and further south lies
Wat Phanan Choeng. Opposite the monastery on the west bank of
the river lies
Wat Rattanachai (Wat Jin).

In situ is a large and prosperous monastic complex. The ordination hall (Th:
ubosot)
stands in the classic east-west alignment facing the Pa Sak river. The ubosot, built in the
Late Ayutthaya style, has two elevated porches each with four columns supporting the
two-tiered roof. Each porch has two entries. The southern and northern walls have five
rectangular windows. The structure is surrounded by an inner wall, called kamphaeng
kaeo (crystal wall), separating the monastic world from the secular world. The site has
numerous chedis and open-sided pavilions (sala). A shrine is dedicated to King Taksin,
commemorating his escape from the area here through the Burmese encirclement in
December 1766, and his come back to the former war zone after the fall of Ayutthaya in
1767 to oust a Burmese proxy at Pho Sam Ton and to restore the internal order in Siam.
He established the capital in Thonburi and reigned for 15 years. The monastery was
established in the early Rattanakosin period, during the reign of Rama I.

Ko Kaeo or Crystal Island is mentioned a few times in the Royal Chronicles of
Ayutthaya. Ayutthaya was on three sides surrounded by the Lopburi River, but the
eastern city border was its weakest point in 1568, as at that time there was only a moat
between Rattanachai Gate in the north and Kaeo Island in the south. (1)  We read in the
chronicles:
"The officials and men of all the cities of Chainat, Suphanburi, Lopburi,
Inburi, Phetburi, Ratburi, Nakhon Nayok, Saraburi, Phromburi,
Sanburi, Singburi, Nakhon Chaisi, Thonburi, and Marit occupied the positions
from the Ratanachai corner down to Kaeo Island; the side so constituted, not
being separated by the river from the land, had only a moat."
[1]

The Burmese in making preparations for the attack of Ayutthaya made earthen
causeways towards the Siamese front ramparts at three points. One of these points was
the corner of Ko Kaeo, where the King of Ava was positioned. [2] The Siamese on
Crystal Island could not withstand the Burmese land attack, additionally supported on
the flanks by a naval force (likely on both canals surrounding Ko Kaeo). The Siamese
fled into their stockade and the wall on the corner of the island was penetrated and
destroyed. The loss of Crystal Island would finally lead to the first fall of the City of
Ayutthaya in 1569.

Phraya Boran Rachathanin wrote in the late twenties of last century that the
ordination hall (ubosot) of the monastery at that time had collapsed nearly completely in
the water. There was a boat ferry between Wat Ko Kaeo and the landing at
Wat Suwan
across the river. (2) [4]

The monastery is indicated on
Phraya Boran Rachathanin's map drafted in 1926 and on
a
map drafted in the mid-19th century.

Footnotes:

(1) After the first fall of Ayutthaya in 1567, King Maha Thammaracha consulted his
"lessons learned" and had the moat widened for military purposes. This moat was called
"Khlong Khu Khue Na" or "Khu Na Muang" (The front city canal). Afterwards the Pa
Sak River changed its flow to this newly enlarged canal and the canal became the current
(new) Pa Sak River.
(2) In Ayutthayan times there were twenty-two ferry routes. In the eastern area, the four
other crossings were: Tha Chang Wang Na to Tha Wilanda, north of Wat Khwang
Fortress to
Wat Taphan Kluea, south of Wat Khwang to Wat Nang Chi and south of
Wat Pa Thon to Wat Phichai. [4] See "The Boat & Ferry Landings of Ayutthaya".

References:

[1] The Royal Chronicles of Ayutthaya - Richard D. Cushman (2006) - page 60 /
Source: Phan Canthanumat, British Museum, Reverend Phonnarat, Phra
Cakkraphatdiphong & Royal Autograph.
[2] The Royal Chronicles of Ayutthaya - Richard D. Cushman (2006) - page 62.
[3] The Royal Chronicles of Ayutthaya - Richard D. Cushman (2006) - page 66 /
Source: Phan Canthanumat, British Museum, Reverend Phonnarat, Phra
Cakkraphatdiphong & Royal Autograph.
[4] อธิบายแผนที่พระนครศรีอยุธยากับคำวินิจฉัยของพระยาโบราฌราชาธานินท์
ฉบับชำระครั้งที่๒และภูมิสถนกรุงศรีอยุธยา (2007) - Explanation of the map of the
Capital of Ayutthaya with a ruling of Phraya Boran Rachathanin - Revised 2nd edition
and Geography of the Ayutthaya Kingdom - Ton Chabab print office - Nonthaburi
(2007) - page 91.
Text & photographs by Tricky Vandenberg - January 2010
Reviewed April 2011
(View of the ordination hall and its inner wall)
(View of the monastery premises)
(View of the monastery premises)
(Phra Tamnak King taksin)
(Buddha image at Wat Ko Kaeo)