The sigmoid colon is located at the end of the large intestine immediately before the rectum, according to Memorial Sloan Kettering Cancer Center. It is the final section of the large intestine and follows the ascending colon, transverse colon and descending colon.
The sigmoid colon holds fecal waste until it is eliminated through the rectum, explains Encyclopedia Britannica. This section is the most common location for the beginning of colorectal cancer, Memorial Sloan Kettering Cancer Center reports. Also, in Western countries, diverticulosis is usually found in the sigmoid colon, states MedicineNet.com. This condition is characterized by small pockets of tissue that push out from the colon. It sometimes causes abdominal pain, constipation and diarrhea.