What structures are anatomical landmark of the promontory?

The promontory is an anatomical landmark located at the anterior part of the sacrum, specifically where the first sacral vertebra protrudes into the pelvic cavity. It serves as a key reference point in obstetrics for measuring pelvic dimensions, as it marks the boundary between the true pelvis and the false pelvis. Additionally, the promontory is important in various surgical procedures involving the pelvis and is associated with surrounding structures, including the iliac vessels and the rectum.