Wayan Swantika of the local archaeology agency says workers digging a drainage basin last week in eastern Denpasar, Bali's capital, at first discovered a large stone about 1 meter (3 feet) underground.
Excavation teams have since uncovered a 57-meter (62-yard) structure that is believed to be the temple's foundation.
The find is still being analyzed, but given the shape and characteristics of the materials used, Swantika says he believes it was built sometime between the 13th and 15th centuries. He added that it is also thought to be the largest ancient temple ever discovered in Bali.
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