'Real Housewives' Turns 100: All The Ladies Who Were On 'Orange County' (PHOTOS)

"Real Housewives" is turning 100.

"Real Housewives of Orange County," the show that launched Bravo's reality phenomenon, is celebrating its landmark 100th episode with a two-hour special featuring interviews with past and present "Housewives" and unseen footage.

"Real Housewives of Orange County" premiered March 21, 2006 with Vicki Gunvalson, Jeana Keough, Jo De La Rosa, Lauri Waring Peterson and Kimberly Bryant as its stars. Since then, a variety of women have called the Bravo series home. Gunvalson is the only remaining original cast member.

Check out all the cast changes below.

SEASON 1

L-R: Vicki Gunvalson, Jeana Keough, Jo De La Rosa, Lauri Waring Peterson and Kimberly Bryant.

Kimberly Bryant, a stay at home mom during the series, only appeared on the first season. She left the series and moved to Illinois, but later made appearances in both Season 3 and Season 4.

SEASON 2

L-R: Vicki Gunvalson, Jeana Keough, Jo De La Rosa, Tammy Knickerbocker and Lauri Waring Peterson

Jo De La Rosa lived with Slade Smiley during the first two seasons of "Real Housewives of Orange County." During Season 2, the two broke up and Jo pursued a career in music. She left the series after the second season, which also introduced Tammy Knickerbocker, but Jo still popped up in Season 3 and 4. Jo and Slade co-starred in the 2008 reality series, "Date My Ex: Jo & Slade." Look for Jo in Bravo's "Real Housewives of Orange County" 100th episode special.

SEASON 3

L-R: Jeana Keough, Lauri Waring Peterson, Quinn Fry, Tamra Barney, Tammy Knickerbocker and Vicki Gunvalson

Quinn Fry and Tamra Barney joined the cast of "Real Housewives of Orange County" for the third season. Quinn was seen dating and looking for a husband. She left the series after her one season, but popped up in Season 4 and 5.

Tammy Knickerbocker also left the series after the third season, but she showed up again at the end of Season 4. A single mom of three, Tammy had an on-again/off-again relationship with Duff, one of Vicki's employees. She also participates in the "Real Housewives of Orange County" 100th episode special.

SEASON 4

L-R: Tamra Barney, Lynne Curtin, Jeana Keough, Vicki Gunvalson, Lauri Waring Peterson and Gretchen Rossi

Season 4 saw the addition of Lynne Curtin and Gretchen Rossi. This was also Lauri Waring Peterson's last season on the series. She left to spend more time with her new family after marrying George Peterson. She returned in a recurring capacity for Season 8 and is interviewed for the 100th episode special.

SEASON 5

L-R: Alexis Bellino, Jeana Keough, Gretchen Rossi, Vicki Gunvalson, Lynne Curtin and Tamra Barney

Alexis Bellino joined the cast during Season 5 of "Real Housewives of Orange County" and original cast member Jeana Keough left early in the season, but has made repeated cameos. Jeana, along with her kids Shane, Kara and Colton, will appear in the 100th episode special.

Lynne Curtin departed at the end of Season 5. Her storylines on the show included her laid back parenting style and being evicted. Lynne appears in the 100th episode special.

SEASON 6

L-R: Gretchen Rossi, Tamra Barney, Vicki Gunvalson, Alexis Bellino and Peggy Tanous

Peggy Tanous, former model, joined the series for the sixth season. It was her first and last on the show.

SEASON 7

L-R: Gretchen Rossi, Alexis Bellino, Heather Dubrow, Vicki Gunvalson and Tamra Barney

Heather Dubrow, an actress and stay-at-home mom, joined the cast of "Real Housewives of Orange County" Season 7.

SEASON 8

L-R: Tamra Barney, Heather Dubrow, Gretchen Rossi, Vicki Gunvalson, Alexis Bellino, Lydia McLaughlin

Season 8, the show's current season, kept the same cast as Season 7 and added Lydia McLaughlin.

"Real Housewives of Orange County" airs Mondays, 8 p.m. ET on Bravo.