Level 1 — Absolute Beginner
Workers in Cambodia found a very old water system under a palace. The system is about 900 years old. It helped move water away from the palace so it would not flood.
The palace is called Angkor Thom. A king built it long ago. His people were called the Khmer. They were very good at moving water.
Workers also found beautiful stones near the water. The stones have pictures carved into them. The pictures show fish, plants, and people playing near water.
Scientists want to use what they found to help people today. When it rains a lot, the old palace still floods. Understanding the old water system may help stop the floods.
- water system
- a set of pipes, canals, or channels that move water from one place to another
- palace
- a large, grand building where a king or queen lives
- flood
- when too much water covers land that is usually dry
- carved
- cut or shaped from stone, wood, or another hard material
- ancient
- very old, from a long time in the past
- canal
- a long, narrow channel dug in the ground to carry water
- scientists
- people who study the world by doing experiments and research
- discover
- to find something that was not known or seen before
Level 2 — Elementary
Archaeologists in Cambodia announced in June 2026 that they had discovered a 12th-century water system beneath the Angkor Thom royal palace. The team is from Cambodia's Apsara National Authority, the government body that looks after the ancient Angkor temples.
The water system includes canals that carried rainwater away from the palace and a reservoir called Pool No. 11. The ancient Khmer Empire built these structures to manage flooding during the rainy season. The system has survived underground for nearly 900 years.
Workers also uncovered carved stone panels near the water channels. The carvings show aquatic animals and people enjoying leisure time near water. These panels give us clues about daily life in the Khmer royal court.
Researchers plan to study the design of the ancient drainage system to help solve a modern problem. Heavy rains still cause flooding at the Angkor World Heritage Site every year. Understanding how the old system worked could help engineers design better drainage today.
- archaeologist
- a scientist who studies history by digging up and examining old objects and structures
- reservoir
- a large natural or man-made lake used to store water
- Khmer Empire
- a powerful ancient kingdom in Southeast Asia that built the Angkor temples
- canal
- a man-made channel dug in the ground to carry water
- drainage
- a system for carrying away extra water so that land does not flood
- heritage site
- a place that is protected because of its historical, cultural, or scientific importance
- aquatic
- relating to water or living in water
- leisure
- free time when you can relax and do activities you enjoy
Level 3 — Intermediate
Cambodia's Apsara National Authority announced in June 2026 that excavations beneath the royal palace zone of Angkor Thom had uncovered a well-preserved 12th-century hydraulic system. The find includes a network of drainage canals and a large reservoir designated Pool No. 11, buried under several metres of sediment for nearly nine centuries.
Angkor Thom was the last great capital of the Khmer Empire, constructed around 1190 CE under King Jayavarman VII. The city was home to a sophisticated water management network that supplied drinking water, irrigated fields, and controlled monsoon runoff across a metropolitan area that may have housed over a million people at its height.
Among the most striking elements of the discovery are carved stone panels depicting aquatic life and scenes of courtly leisure near water. Archaeologists believe these carvings suggest that water features served both a practical drainage function and a ceremonial role in Khmer palace culture. The team is now studying inscriptions on the panels to date the structures more precisely.
The research team hopes that understanding the original hydraulic geometry of the canals and reservoir will help engineers design a modern drainage intervention to reduce the seasonal flooding that still threatens the integrity of the Angkor World Heritage Site each rainy season.
- hydraulic system
- an engineered network of channels, pipes, or reservoirs used to control and move water
- excavation
- the process of carefully digging in the ground to uncover buried structures or artefacts
- sediment
- material such as sand, clay, or silt that settles at the bottom of a body of water or is deposited by water over time
- irrigation
- the controlled supply of water to farmland through channels or pipes
- monsoon
- a seasonal wind pattern that brings heavy rainfall, especially in South and Southeast Asia
- inscription
- words or symbols carved or written on a hard surface such as stone
- ceremonial
- relating to formal rituals or official occasions, often with symbolic importance
- integrity
- the state of being whole and undamaged; the condition of a site remaining in its original form
Level 4 — Advanced
An excavation led by Cambodia's Apsara National Authority Department of Temples and Archaeology has yielded a remarkably intact 12th-century hydraulic infrastructure beneath the royal palace zone of Angkor Thom. The exposed remains comprise an anastomosing network of drainage channels and a basin catalogued as Pool No. 11, preserved beneath several metres of alluvial sediment accumulated over nearly nine centuries of disuse.
Angkor Thom was the terminal great capital of the Khmer Empire, commissioned by Jayavarman VII circa 1190 CE within the broader Angkor hydraulic city, whose engineered landscape encompassed baray (rectangular reservoirs), srah (ponds), and canals spanning hundreds of square kilometres. This hydro-engineering system is widely regarded as one of the most ambitious pre-industrial water-management achievements in human history, sustaining a metropolitan population estimated at over one million.
The discovery of finely worked lithic panels among the structural debris, bearing iconographic programmes featuring piscine fauna and aristocratic leisure activities, raises questions about the dual functional-ceremonial role of palace water features. These carvings may be cross-referenced with existing epigraphic evidence from nearby temple complexes such as Preah Khan and Ta Prohm to establish a more precise chronology of the palace precinct's hydraulic development.
From a conservation science perspective, the stratigraphic profile of the excavated sediment column offers a potential proxy record of palaeoclimatic variability across the late medieval period. Concurrently, the recovered hydraulic geometry of the drainage channels can be computationally modelled to design a contemporary drainage intervention, aimed at mitigating the seasonal inundation that continues to threaten the structural integrity of the broader Angkor World Heritage Property.
- anastomosing
- describing a branching network where channels divide and reconnect, forming a lattice-like pattern
- baray
- a large rectangular reservoir constructed by the Khmer Empire to store monsoon water for year-round use
- epigraphy
- the academic study of inscriptions carved or written on stone, metal, or other durable materials
- stratigraphic
- relating to stratigraphy, the study of rock and soil layers to understand chronological sequence
- palaeoclimatic
- relating to ancient climates and weather patterns from the distant geological past
- iconographic
- relating to the use and meaning of images and symbols in artistic or cultural representation
- hydro-engineering
- the branch of civil engineering concerned with the design and management of water resources and infrastructure
- inundation
- the flooding of land by water, especially as a result of heavy rain or the overflow of a water body
