Gabi, the world's first elephant conceived through in-vitro fertilization (IVF), celebrated her 13th birthday Monday with 50,000 visitors at the Gaziantep Zoo in southeastern Turkey.

Entrance to the zoo was free on Monday, due to the National Sovereignty and Children's Day celebrated each year on April 23.

Guests fed Gabi special treats, including a heart-shaped "cake" of fruits and vegetables.

"We prepared a birthday cake to show how we've raised Gabi from a tube baby to the age of 13, and how important she is to us," Gaziantep Mayor Fatma Şahin told the Doğan News Agency at the event.

"You can see the happiness and excitement in the eyes of our children," she added.

The Gaziantep Zoo welcomes 3.5 million visitors a year, making it the fourth largest zoo in Europe, Şahin said.