The Eastern Gate and Rampart
Si Mahosot is an ancient town, surrounded by moats and ramparts in rectangular shape (700 x 1,500 meters). There is a linking ditch connect the south and the north moat. The moats dug into laterite about 15-20 meters in-width. The ramparts were built by laterite that dug from the moats which is about 10 meters wide and 5 meters high.
The aerial photo of Si Mahosot ancient town
The south moat and rampart
Map of Si Mahosot ancient town show the location of The Eastern Gate and Rampart 
Different from other parts of ditches and ramparts of the ancient town of Si Mahosot, at this spot a ‘horseshoe-like shaped ditch’ was additionally dug out and flanked by two high earthen mounds, served as a sentry station. It is conjectured that the eastern entrance to the town could be accessed by way of a movable wooden ramp-bridge across the centre of the upper ‘horseshoe’ ditch, and a wooden watch towered gate was constructed at this place in the period of building the moated town, during the late 6th century CE.
The reconstructed sketch of the Eastern Gate and Rampart
According to the Royal Gazette no 52, dated March 16th, 1935, The Fine Arts Department announced that this monument has been listed as the nation’s historic site.