Unlike the mobile small intestine, most of the large intestine is relatively fixed in place. There is no mesentery connected with the cecum or the ascending and descending colon, while the transverse colon is enclosed by a mesentery called the transverse mesocolon and is modestly mobile.

The ascending colon and descending colon both lie mesoperitoneally (covered by the peritoneum from three sides) in the lateral gutters of the abdominal cavity, while the transverse colon and cecum lies intraperitoneally (enclosed by the peritoneum from all sides).

The splenic flexure is anchored by peritoneal folds, connecting it with the diaphragm and spleen. As the descending colon crosses the iliac crest, it becomes the sigmoid colon which is completely covered by the peritoneum and is relatively mobile due to its long mesenteric attachment (sigmoid mesocolon).

The large intestine generally has a larger lumen than the small intestine, except the descending colon, which may be the same diameter when empty.

Three main distinguishing features of the large intestine:

Taenieae coli - three longitudinal muscle bands situated equidistantly around the circumference of the colon;
Haustra - sacculations seen in the colon wall that give the intestine its segmented appearance; the wall of the large intestine is formed into pocket-like sacs or small segmented pouches caused by sacculation; contractions of muscle fibers in the teniae provide this intestine segmentation and the teniae are shorter than the length of the intestine;
Epiploic appendices - the visceral peritoneum contains tiny fat-filled droplets or pouches called the epiploic appendices, and they hang down mainly along the free and omental taeniae and are attached to them; these appendices can become inflamed - this condition is called epiploic appendagitis.

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Features of large intestine