The doors you see in Aria's bedroom leads to Spencer's bedroom on set.
In the pilot the role of Mrs DiLaurentis is played by Anne Marie DeLuise, however she was recast and now the role is played by Andrea Parker.
Lucy Hale once said in an interview that the most annoying thing about the show is the opening title sequence where her finger is off center of her mouth.
The series doesnt follow the books, and so some characters who were killed on the show (for example Maya) werent killed off in the books, but with some characters like Toby (who in the books was killed off) it is vice versa. The show creators did originally plan to kill Toby off but didn't due to his character's popularity on the show.
The girls are in the 12th grade for a total of 49 episodes spread across three and a half seasons.
Tammin Sursok originally auditioned for the role of Spencer Hastings, but got casted as Jenna Marshall instead
Between Tammin Sursok (Jenna) and Sasha Pieterse (Alison) there are almost 12 years apart. Tammin was born in August 1983 and Sasha in February 1996.
On Tuesday, August 11, 2015, in the season 6 mid-season summer finale "A" was finally revealed, along with "Red-Coat" and "The Black Widow" "A" is CeCe (or Charles/Charlotte) and "Red-Coat" and "Black Widow" are both Sarah Harvey.
Alexis Denisof was originally cast as Byron, but before the pilot was replaced by Chad Lowe.
In the third season, the first time you meet Ezra's child, Malcolm, he was a little boy in school. The second time he is at his house and the child is completely different.
All the liars have, at one point or another, suspected their love intrests of being A or on the A team. Both Toby and Caleb in season one, Paige in season three and Ezra in season four
Troian Bellisario, Ashley Benson, Shay Mitchell, and Lucy Hale all are very good friends in real life.
Ashley Benson and Lucy Hale both appear in How I Met Your Mother (2005)
Tammin Sursok (Jenna Marshall) and Sasha Pieterse (Alison DiLaurentis) were both born in Johannesburg, South Africa
Almost every cast member knew who A was except Lucy Hale. They were afraid she would tell someone else because she's not so good in keeping secrets. She stated that herself in an interview.
Troian is the oldest of the girls
Lucy Hale (Aria) auditioned for the role of Hanna, which eventually went to Ashley Benson.
"Pretty Little Liars" is the longest running show ever on ABC Family
Tammin Sursok was almost 25 years old when the she filmed episode 1.2 The Jenna Thing (2010) and Sasha Pieterse was 13 years old.
Lucy hale (Aria), Sasha Pieterse (Alison), Tyler Blackburn (Caleb) and Janel Parrish (Mona), all have an album.
Actress Bianca Lawson and actor Cody Christian both starred in MTV's Teen Wolf (2011).
Because the first few seasons of the show are stretched over one school year, it would technically only be 2011 or 2012 in Rosewood up until the season 6a ending then there was a time jump and now time will catch up
The person who originally played Alison's brother Jason DiLaurentis was Parker Bagley, after season one Drew van Acker took over the part.
Vanessa Ray and Troian Bellisario share several scenes. They have appeared in Suits too but never together. Ironically, both women played Patrick J. Adam's love interest who is Troian's real life fiancé. Patrick has appeared in a bit role in Pretty Little Liars as Ezra's friend, but not shared scenes with either Troian or Vanessa.