"I could tell immediately by her poise and movement on the stage that she (Stahl) was at ease with herself," said Pat Massa, one of the judges.
"They all did a nice job," added Carol Garling, also a judge.
Stahl replaces last year's queen, Jacqueline "Nicki" Layton.
Starting at Shippensburg University as a freshman this year, Stahl plans to major in veterinarian medicine.
"I'm happy for her because she met a goal," said her mother, Twila Stahl.
The title of Franklin County Fair Princess went to Kelly Barnes, 19, of Scotland, Pa.
As princess, Barnes would take over the duties of fair queen if Stahl can't fulfill them.
A junior at Delaware Valley College, Doylestown, Pa., Barnes said she plans to attend graduate school and eventually become an animal nutritionist.
Active in school, Barnes has served as her class president since freshman year, is co-editor of the school's yearbook staff, and plays volleyball.
"I'm really excited. I love the fair and I love Franklin County," she said.
St. Thomas, Pa. resident Elizabeth Strock, 19, was named first runner-up.
"I was so nervous," she said. "This is the first year I've been in the pageant and the first time I've done anything like this."
A leukemia survivor, Strock works part-time at the St. Thomas Library. She eventually plans to go to college and wants to work at the Library of Congress in Washington, D.C.
Crissy Crowe, 17, of Waynesboro, Pa., and Jenifer Lee Garber, 17, of Waynesboro, also ran for the fair queen title.
Besides her duties during the week of the fair, the queen attends several events throughout the year including parades, festivals, local banquets, picnics and other events.
The Franklin County Fair, held on the grounds of the Chambersburg Rod and Gun Club on Pa. 995, continues today commemorating Waynesboro's Bicentennial with a special exhibit in the arena.
On Wednesday, the 40th annual 4-H and FFA tractor driving contest will be held in the arena at 9 a.m.
A rodeo starting at 7 p.m. in the arena is the highlight on Thursday along with a motorcycle display, a dog show and dairy show.
The antique car and equipment show will be held from 5 to 9 p.m. on Friday and a motorized pulling event gets underway at 6 p.m.
The fair ends on Saturday with a rabbit show and youth horse show, a light and heavy horse pull at 6:30 p.m. and a gospel music concert featuring the group Perfect Heart at 6:30 p.m.