In 1191, five year after the building of Ta Prohm, the king dedicated this temple to be the shelter of the idol of his father, Dharnindravarman II, in the likeness of Bodhisattva Lokesvara. The causeways lead to the temple are bordered by the same figures carrying a Naga symbolized the Churning the Sea of Milk. This architectural element was the mark of a royal city. It may have served as a temporary residence of King Jayavarman VII while he was rebuilding the capital after the Charms sacked Angkor in 1177. Preah Khan is the name of the sacred sword, the safeguard of Cambodia, which is preserved in the palace of Phnom Penh, it seems that there is a connection between this precious arm and the name of the monument, a name which is not unique among the temple of the country. It is among the largest monuments. It includes a set of four concentric enclosures are longer to the east and west (800m by 700m, 7m high), giant Garudas and serpents are decorated every 50m around the 3km long wall. The wall of central complex forms quadrilateral 250m by 175m with Gopuras or entrance pavilion -  with three passages. The avenues 250m long towards the entrances.

The inscription found in 1939 tells us: there were 430 images with 5,324 villages totaling 97,840 tax payers of box sexes. The stele enumerates the monuments attached to Preah Khan, including among other temples: Krol Ko, Ta Som and the little Sanctuary - Neak Pean "an eminent island, whose Charm lies in its surrounding ponds which cleans the soil of sins from those who visit it". Among the many religious foundation of the King listed on the stele of Preah Khan: Lopburi, Supan, Ratburi, Pichburi and Muong Sing, all today in Thai territory. Perhaps it was to house statues of this type that some ot the provincial sanctuaries were built- Sanctuaries whose style indicates that they belonged to the time of Jayavarman VII e.g. Wat Nokor at Kompong Cham, and Ta Prohm at Bati. This stele mentions 121 resting house constructed along the roads that fanned out over the kingdom:

• 57 on the road from Angkor to the capital of Champa

• 17 on the road from Angkor to Phimai (200km)

• 46 leading to some cities which we still do not know

• one at Phnom Chisor.

They were spaced from 12 to 15km apart; we know 8 of the 17 which bordered the road from Angkor to Phimai. Beng Mealea, Ta Prohm, Preah Khan, Banteay Chmar, each has its own, constructed in the temple enclosure to the East entrance. This system was still in existence a century later as Chinese envoy Chou Ta Kuen wrote in his account of his voyage: "A long the important roads there are resting places similar to our posting houses".

In 1191 after only ten years of the reign, when the program was not yet completed, according to the stele at Preah Khan, there were more than 20,000 idols in gold, silver, bronze and stone spread all over the kingdom. The service of their cult required 306,372 servitors, living in 13,500villages and consuming 38,00 tons of rice yearly.

The creation of these resthouse went hand in hand with a widespread campaign for sanitation which evidenced by the 102 hospitals scattered over the country. These shelters for the sick were certainly built of light materials. We know the location of 33 hospitals of Jayavarman VII, that is a third. The foundation steles give us the interesting in formation about their organization; the inscription tells us that the hospital is placed under the auspices of Buddha- the healer, Bhaisaj Yaguru Vaiduryaprabha "the master of remedies, with the shinig beryl" whose statue was one of the most popular Buddha and still is today in China and Tibet.

The four castes could be cared for in these hospitals. There were:

2 doctors, each assisted by a man and 2 women, 2 store-keepers with the job of giving of the fuel and water as well as for cleaning the temple, 2 servitors to prepare the offerings for Buddha, 14 hospital attendants, 6 women to heat the water and to grind the medicines, 2 women to pound the rice. The total number of workers who were housed was 33. Besides them there were 66 lodged at their own expense, making a total of 99.

Rice for offerings to the divinities was fixed at a bushel a day, and the leftovers were given to the patients. The list of provisions taken three times a year in the Royal stores included:

Honey, sugar, camphor, sesame, spices, black mustard, cumin, nutmeg, coriander, fennel, cardamon, ginger, cubed, vetiver, cinnamon, myrobalan, jujube, vinegar, the quantities of each of which are exactly stated.

Besides the provincial hospitals whose management we have just described there were also a certain number of more important establishment in the big center, especially at Angkor. The stele says: The government health service consumed 11,192 tons of rice annually, produced by 838 villages with a population of 81,640 people. The hospital 3,402kg nutmegs, 48,000 febrifuges, 1,960 boxes of salve for hemorrhoids and so on in proportional amounts.