A filthy place can be described as a CESSPOOL, SEWER, STY, PIGSTY, PIGPEN, or rath. A CESSPOOL is an underground tank used to collect sewage and wastewater. A SEWER is an underground pipe system that carries wastewater away from buildings. A STY is a small pen or enclosure for pigs. A PIGSTY is a small building or area where pigs are kept. A PIGPEN is an enclosed area where pigs are kept. A rath is an ancient Irish fortification consisting of a circular wall of earth and stones.