In a sea of duplicate facial features, the sleepy town of Igbo-Ora in Nigeria's southwest Oyo state came alive over the weekend with laughter, music, and celebration at the annual Twins Festival.

The festival featured a procession of twins of various ages, parading in pairs, taking photos, dressed in matching clothes and accompanied by drummers and dancers.

The five-day event showcased the unique bond between twins.

Opeyemi Daniel, who grew up as the only single birth among five sets of twins in her family, celebrated at the festival with her own twin girls.

"I had a special interest for twins when we were young. I am the only one that is not a twin among my mother's children. My mother had twins five times. I used to be happy when I saw them. So I hoped that when I also have twins I will endow them with the same clothes and same shoes, so I wanted twins and I have them now," she told Reuters.

Twins are common in the Yoruba ethnic group that dominates southwest Nigeria.

A 1970 study by a British gynecologist found that around 50 sets of twins were born out of every 1,000 births in the southwest - one of the highest rates of twin births in the world.

Even among Yoruba people, Igbo-Ora is considered exceptional, with at least one twin birth in every family.

Kehinde Oladele-Oguntoye, founder of the World Twins festival, said: "For this event we are not projecting a particular amount of twins, but for the past events, I can remember like 3 or 4 years ago, we recorded 2,034 sets of twins in this same field here."

The names Kehinde and Taiwo, given to all Yoruba twins, are commonplace in Igbo-Ora, reflecting the town's high twin birth rate.

In Yoruba culture, Kehinde, the second-born twin, is considered the elder, based on a century-old myth.

Igbo-Ora's king, Jimoh Olajide-Titilayo, said: "All the households here, each compound have twins in their midst, and this is something unique that if you call 'Kehinde' you will see so many 'Kehindes' looking in your direction. The same thing happens to Taiwo."

Locals believe the high rate of twin births is linked to okra leaf and amala, a local dish made from yam and cassava flour.

However, doctor Gafar Amoo said research suggests genetic factors are more likely responsible.

"There has been a lot of efforts in the past by scientists, by medical researchers to unravel the mysteries behind the multiple pregnancies in Igbo-Ora, and one of the major factors that was identified is the issue of genetic factors," he said.

This year's festival saw fewer twins in attendance compared to previous years.

Organizers aim to set a Guinness World Record for the largest twin gathering and secure UNESCO recognition as a cultural heritage event.