Welcome to Igbo-Ora, a town in Oyo State, southwest Nigeria. A sign at the entrance greets visitors with the words “Twins Capital of the World”. The town is rural, and most of its people are farmers and artisans, yet it has drawn the attention of scientists, journalists and tourists from around the world.

Twins are rare in most places. The global average is around 12 sets per 1,000 births. In Igbo-Ora, research by the British gynaecologist Patrick Nylander recorded an average of 45 to 50 sets of twins per 1,000 births. More recent studies reported about 1 twin set in every 22 births, roughly four times higher than anywhere else in the world. For comparison, the United States records about 33 per 1,000 births.

Nobody has proven the exact cause. Nylander found that the high rate is almost entirely due to non-identical (dizygotic) twins, which points to a strong genetic influence. This fits a wider pattern, because twinning is common among the Yoruba people, the dominant group in the region. Some reports also note that twins who marry twins often have twins.

Diet is the popular local explanation. Many residents believe that a kind of okra leaf called ewe ilasa helps women conceive twins. The foods blamed or credited include okra soup (ilasa) and yam. No scientific evidence has confirmed this, and the genetic explanation remains the leading one.

Twins hold a special place in Yoruba tradition. The first-born twin is called Taiwo (Taye) and the second Kehinde, and families have long praised twins through oriki, traditional poetry. That heritage is why the town celebrates its reputation so openly.

Each October, Igbo-Ora hosts the World Twins Festival. It began about ten years ago as the Naija Twins Festival and was later repackaged for global participation. The 2023 edition featured cultural dances, a twins’ parade, a talent show and oriki praising twins. At the 2019 festival, the visiting Yoruba king Oba Kehinde Gbadewole Olugbenle, himself a twin, said there is hardly a family in Igbo-Ora without a twin. Organisers want Igbo-Ora to become the foremost twins tourism destination in the world, and have talked about pursuing a Guinness World Record listing.

Igbo-Ora shows how genetics, culture and community pride can turn a small town into a place known worldwide. Other twin-heavy communities exist, such as Kodinji in India and Cândido Godói in Brazil, but none compares with Igbo-Ora.