
George B. answered 12/20/22
MD
technically the answer is the pelvic cavity, however there is no separation it is all one cavity often referred to as the peritoneal cavity.
above the cavity is the thoracic cavity and that separated from the abdominal cavity by the diaphragm, the muscle used to breathe.
Behind the peritoneal cavity lies the retroperitoneal cavity which is separated from the peritoneal cavity by the retroperitoneum, which has two layers. the pancreas,The Esophagus, part of the stomach, the kidneys, the adrenal glands, the ureters, parts of the colon are in this cavity.