These swimming-pool-like ponds were likely used by monks from nearby Kaparamula residence hall. Water entered the larger pond through the mouth of a makara (a mythical hybrid beast featuring the body of a fish, the mouth of a crocodile and the trunk of an elephant) and then flowed to the smaller pond through an underground pipe. Note the five-headed cobra figure close to the makara and the nearby water-filter system, both at the northwestern end of the ponds.
Although they are referred to as twins, the northern pond, which is 28m in length, is smaller than the 40m-long southern pond.