Prasat Prang Ku is an important sanctuary within the “Arokhayasala” network, commissioned by King Jayavarman VII of the Khmer Empire during the 18th Buddhist century. These establishments were built across the Mekong Basin and northeastern Thailand as healthcare and welfare centers, while also supporting the spread of Mahayana Buddhism.The concept of “Arokhayasala” was not merely a hospital system, but a religiously integrated public health model. It was centered on the worship of the Medicine Buddha, Bhaisajyaguru (the Healing Buddha). Healing practices combined herbal medicine, ritual ceremonies, and spiritual merit-making, reflecting a holistic approach where religion and medicine worked together. These complexes therefore functioned simultaneously as hospitals, shelters for the sick, and religious sanctuaries.

Architecturally, Prasat Prang Ku follows the standard Khmer temple layout. It consists of three prasats aligned on an east–west axis, with the central tower serving as the sacred core. In front of the sanctuary lies a “bannalai” (library building) used for storing sacred texts and ritual objects. The complex is enclosed by a laterite boundary wall marking the sacred precinct.The construction materials reflect Khmer engineering adapted to local resources: laterite, widely available in northeastern Thailand, was used for structural cores due to its durability, while sandstone was reserved for detailed carvings such as lintels, pediments, and door frames. These carved elements display refined religious iconography and artistic precision.

The site is primarily associated with Bayon-style Khmer art, characterized by serene and compassionate expressions, especially the iconic smiling faces associated with Mahayana Buddhist symbolism. This artistic style aligns with the humanitarian purpose of the Arokhayasala system, emphasizing compassion and healing rather than royal grandeur.Compared to other Arokhayasala sites in the region, such as those associated with Phimai or Phanom Rung, Prasat Prang Ku is smaller in scale but retains the essential architectural components. Its three-prasat arrangement represents a shared design identity found across more than a hundred Arokhayasala sites distributed throughout the Khmer sphere.From a historical and archaeological perspective, the site confirms that Prang Ku District was once part of the Khmer Empire’s provincial network, integrating religious, medical, and administrative functions. This highlights its significance both locally and within the broader Southeast Asian historical landscape.

Today, despite being over a thousand years old, Prasat Prang Ku has been partially preserved and restored. Its remaining structures continue to serve as an important cultural, historical, and educational landmark in Sisaket Province, Thailand.