Built in the Khmer Empire under King Suryavarman II, Angkor Wat is the largest religious complex in the world, and it reads as a whole at both structural and landscape scale.

The structural technique is dry stacking: the sandstone blocks are laid without mortar, cut precisely and fitted together — in places with joints between them. Khmer architecture does not use the true (keystone) arch; the interior passages and galleries are roofed with corbelled vaults formed by successive courses of stone oversailing inward. This keeps the spans narrow and divides the space into linear galleries.

The plan is a diagram of Hindu cosmology: at the centre, five towers representing Mount Meru, the axis of the universe, rise in a quincunx (four corners plus centre) on a rectangular base. The whole complex is encircled by a wide moat and successive enclosing walls; the visitor crosses a causeway and proceeds toward the centre through nested courtyards. The real engineering, though, is in the invisible infrastructure: Angkor is part of a hydraulic system of vast reservoirs (baray) and canals; the building is the core of a city-temple landscape integrated with water management. Angkor Wat thus unites stone-stacking technique, the mandala plan, and water engineering at a single scale.