Many thousand monks and staff lived at the Abhayagiriya proper bathing facilities were necessary and the Twin Pond is the most impressive of the several such baths in the monastery. The Twin Ponds date from the 8th century, the larger one being built first while the smaller one was added later. The larger pond is 132 feet long while the smaller one is 91 feet long and both are 51 feet wide. Each pond has a flight of stairs at each end as well as steps around their sides allowing that many people to bathe at the same time.

         The size of some of the stones and their finish is impressive. At the far end of the ponds the sophisticated filtering device can be noticed. Water flowed into the first part where sticks and leaves were trapped and then into the second part which allowed silt to settle before finally the water flows into the pond via a dragon-headed spout. Next to this spout is an impressive Naga stone as they were believed to live in the watery depths and stones honouring them were always placed near sluices, fountains and waterspouts. The water then flowed from the smaller into the larger pond through a pipe some way towards the bottom of pond. After being used for washing the water was carefully channelled out to the adjoining rice fields. Near the North West corner of the ponds is a spout where people washed their feet before bathing.