WAT KO KAEO (วัดเกาะแก้ว)
View of the monastery premises
Wat Ko Kaeo or the Monastery of the Crystal Island is an active temple located off
the city island in the eastern area of Ayutthaya 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 Ratana Chai (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 Ratanachai 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]

Wat Ko Kaeo is indicated on Valentyn's map "Groote Siamse Rievier Me-Nam Of Te
Moeder Der Wateren In haren loop met de vallende Spruyten Verbeeld" as Wat
Kokeuw. [5]  We find the monastery also on a
mid-19th century map and on Phraya
Boran Rachathanin's map drafted in 1926.

The monastery is located in Geo Coord: 14° 20' 49.92" N, 100° 34' 60.00" E.

Footnotes:

(1) After the first fall of Ayutthaya in 1569, King Maha Thammaracha consulted his
"lessons learned" and had the moat widened for military purposes. This moat was called
"
Khu Khue Na" or "Khu Na Muang" (The Front City Canal).
(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] Athibai Phaenthi Phra Nakhon Sri Ayutthaya kap khamwinitjai khong Phraya Boran
Racha Thanin - 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.
[5] Valentyn, François - Oud en Nieuw Oost-Indiën (1626) - Deel 3 - Boek 6 -
Beschryvinge van Siam en onsen Handel aldaar.
Text, maps & photographs by Tricky Vandenberg - January 2010
Updated April 2011, December 2014
View of the monastery premises
Phra Tamnak King Taksin
(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
(Buddha image at Wat Ko Kaeo)
Detail of François Valentyn's map published in 1724
Detail of a 19th century map - map is orientated S-N
Detail of Phraya Boran Rachathanin's map - Anno 1926
Detail of a 2007 Fine Arts Department GIS map
(Detail of François Valentyn's map published in 1724)
(Detail of a 19th century map - map is orientated S-N)
(Detail of Phraya Boran Rachathanin's map - Anno
1926)
(Detail of a 2007 Fine Arts Department GIS map -
Courtesy of the Fine Arts Department - 3th Region)