Saudi Arabia ranks number one on a new list of the most religious countries in the world.

“A fierce religious identity dominates the Sunni-majority nation, with principles of the Koran, conservative Sunni teachings known as Wahhabism, and strict Islamic Sharia law present in all aspects of life,” according to a just-published survey in U.S. News and World Report.

“Most of the men who carried out the 9/11 attacks came from Saudi Arabia.”

The religion ranking was determined after surveys were completed by over 21,000 citizens in 80 countries.

“Overly restrictive policies may have given rise to dissident groups like al-Qaida that led the deadly 9/11 terrorist attack on the United States and another in 2003 in capital city Riyadh,” U.S. News said of Saudi Arabia. “Most of the men who carried out the 9/11 attacks came from Saudi Arabia.”

Many of the countries on the 2017 top-10 list are Middle Eastern nations.

Related: Why Islam May Surpass Christianity as World’s Largest Faith

In order, here are the top 10 most religious countries:

  • Saudi Arabia
  • Israel
  • Iran
  • India
  • United Arab Emirates
  • Pakistan
  • Jordan
  • Egypt
  • Oman
  • Turkey

The Muslim-dominated countries among those 10 are Saudi Arabia, Iran, United Arab Emirates, Pakistan, Jordan, Egypt, Oman, and Turkey.

In Israel, the majority of people are Jewish. In India, Hinduism remains the major religion.

These countries rank anywhere from 22 to 79 on the U.S News list of overall “best countries.”