Khao Noi Si Chompu Castle

Khao Noi Si Chompu Castle is a Khmer Hindu shrine on a hilltop in Aranyaprathet district, Sa Kaeo province, built around the 7th century AD — making it one of the oldest Khmer religious sites known in Thailand. Despite the English name, it isn’t a fortress: “castle” is a loose rendering of prasat, the same word used for temple-mountains across the Khmer world. Entry is free, daily 08:30-16:00.

The site originally held three brick prangs (towers) arranged in a row on a shared platform, facing east — a standard layout for early Khmer shrines. Only the central prang still stands today, extensively restored by the Fine Arts Department; the north and south towers survive only as foundations. Carved sandstone lintels recovered from the towers, including one showing makara figures disgorging medallions, are now held at the Prachinburi National Museum rather than displayed on-site. The hill itself rises about 130 metres, reached by a 254-step staircase or the access road.

What makes the site significant isn’t its scale — it’s a single restored tower on a modest hilltop — but its age and what was found here. Inscriptions studied at the site date to the 7th century, among the earliest evidence of Khmer religious building in what’s now Thailand, predating the Angkor-era temples scattered across Isan by several centuries. Archaeologists also recovered lingas and pedestal fragments at the site, many found shattered, suggesting the shrine was deliberately damaged at some point in its history.

Insider Tip: This is a small site — the central prang and its platform are what you’ll see, not a sprawling temple complex. Combine it with other Khmer ruins in the province, such as Prasat Sadok Kok Thom or Khao Loan Castle, rather than making the drive out here alone.

Watch out: Don’t expect defensive walls, ramparts, or watchtowers — despite the name, there’s no fortress architecture here. If you’re picturing a hilltop fort, you’ll be looking at a single stone tower instead.

Aranyaprathet town and the Rong Kluea border market sit nearby, but this hilltop shrine itself has no direct connection to the modern border crossing — it predates the current Thai-Cambodian frontier by well over a thousand years.