Prasat Tonle Snguot
The "ng" is to be pronounced similar tu "n" in "English" or "ng" in "being" but without a vowel sound in front of it. "Snguot" sounds like "sngoort". It means "dried". "Tonle" means "lake". So this is the "Prasat tower of the dried up lake", according to its modern name.
Prasat Tonle Snguot is a small ruin rarely visited. There is not much to see here except a broken - or nearly split - single temple tower. It is located a few hundred metres north of the North Gate of Angkor Thom and originates from the same period, this means the reign of King Jayavarman VII. More precisely, Prasat Tonle Snguot is from the end of the 12th century.
The Prasat was the sanctum or worshipping hall of a functional building, a hospital, one of the 102 so-called "Arogyasalas" (also romanized "Arogyashalas" or "Arokhayasalas") Jayavarman VII claimed to have founded, at least one in each province. The Sanskrit term "arogya" literally means "not-sick".
Four of those hospitals surrounded Angkor Thom, in all four directions. But they were not placed exactly axial, and they were located in different distances between half a kilometre and one kilometre. The Arogyasala in the East is the best preserved one and usually only called "Chapel of the Hospital". The southern one, opposite the Angkor Wat, is Ta Prohm Kel. The one in the west is a little bit far and outside the Angkor Archaeological Park. Prasat Tonle Snguot was the hospital chapel to the north of Angkor Thom. Some more of them are known throughout Cambodia and North East Thailand, for example three along the road to Phimai on Thai territory, one newly discovered.
The number of altogether 102 hospitals built by Jayavarman VII is given in a famous inscription of Ta Prohm. Arogyasala (hospitals) as well as Vahni-Grihas (fire-chambers), mentioned in a contemporary inscription at Preah Khan, are rare examples of public instititions in the medieval Angkor empire that are known from both epigraphic and archaeological evidence. An archaeological research titled "Angkor Medieval Hospitals Archaeological Project" started 2006 to examine the exact location of wooden hospital halls in the precincts of the Hospital Chapel to the west of Angkor Thom.
Maybe, it's better to visit this temple during noon, but any time of the day will be almost even good. You do not need an Angkor ticket in this area.