O’Nell Starkey is a visual learner, so when she had to track her daily cervical position for a midwifery school assignment, she opted to take a photographic approach.

“I decided to use a speculum and look at my cervix every day in addition to feeling it with my finger and observing the changes in the fluid it produces,” Starkey tells SELF. “I had my partner take a photo of my cervix every day for a cycle so I could see the changes it was going through.” She posted the photos online thinking maybe some of her midwife colleagues would find them interesting.

Surprisingly, others on the Internet took notice, so Starkey opened it up to let other women submit photos of their cervices. That was seven years ago. Now The Beautiful Cervix Project (beautifulcervix.com) hosts a large gallery of images and has had millions of visitors.

The process of photographing one’s own cervix—the lower part of the uterus that connects to the vagina—is less involved than you might imagine. Starkey explains that all you need is a speculum, like the one your gynecologist uses to open the vagina for exams (but inserted upside down, so you can reach the handle through your legs), a flashlight, and a camera. The one on your iPhone will do. (You can buy a self-exam kit on the site.)

“Women who are inspired to learn more about themselves volunteer to contribute to the project and take the photos themselves (or have a partner or friend or doctor take the photos) in the comfort of their own homes,” Starkey says. Some choose to submit just a single image, such as the cervix after childbirth, during a Pap smear or after a LEEP procedure to remove precancerous cells. Others send in series showing how the cervix changes over the course of one menstrual cycle. There are pictures of a cervix pre- and post-coitus, pre- and post-menopause, and ones that show the strings of an IUD peeking through.

Courtesy of The Beautiful Cervix Project

This all might lead you to wonder why. Why photograph your cervix and share it on the web? Starkey has a simple explanation: “Cervices are amazing!”

She’s got a point. They close off the uterus to protect it from infection, they can hold in a growing baby for 10 months, and they can open up—really wide—to let that baby out when it’s time. They really are an underappreciated workhorse of the female anatomy.