Greater omentum

The greater omentum is a large apron-like fold of visceral peritoneum that hangs down from the stomach. It extends from the greater curvature of the stomach, passing in front of the small intestines and reflects on itself to ascend to the transverse colon before reaching to the posterior abdominal wall. It is the first structure observed when the abdominal cavity is opened anteriorly. 

The right and left gastroepiploic (gastro-omental) vessels provide the sole blood supply to the greater omentum. Both are branches of the celiac trunk. The right gastroepiploic is a branch of the gastroduodenal artery, which is a branch of the common hepatic artery, which is a branch of the celiac trunk. The left gastroepiploic artery is the largest branch of the splenic artery, which is a branch of the celiac trunk. The right and left gastroepiploic vessels anastomose within the two layers of the anterior greater omentum along the greater curvature of the stomach.