Wat Nakorn-Kosa is a very ancient and abandoned wat located near Pra Prang Sum Yod, the early 13th century temple, in Lopburi Province (related story on page 29/720).
It has been existed (with different unknown name) since the dawn of Khmer Empire (somewhere between 802-1431) as a shrine for deities derived from Hinduism.
Later on, when the dawn of Khmer Empire faded and Buddhism grew stronger, the place had been changed to a wat and became flourished at its peak in the reign of King Narai the Great of Ayutthaya Kingdom (his story can be read on page 31/762) when he had moved his capital from the city of Ayutthaya to Lopburi and fully renovated Wat and gave it the name Nakorn-Kosa (named after a high noble official's name who was responsible for the renovation).
When the reign of King Narai ended and the next king moved the capital city back to the city of Ayutthaya, Wat became deteriorated and finally deserted as seen in this computer colored photo shown below which was taken in the late years of King Rama V (around early 1900s).
Old records say that originally, the area of Wat was immense but in the reign of King Rama V, he ordered railway tracks constructed that cut through the area of Wat. Some old buildings getting in the way were demolished. All the debris was used for track construction.
(Today)