Today marks the thirty-first installment in a series of articles by HumanProgress.org called Centers of Progress. Where does progress happen? The story of civilization is in many ways the story of the city. It is the city that has helped to create and define the modern world. This bi-weekly column will give a short overview of urban centers that were the sites of pivotal advances in culture, economics, politics, technology, etc.

Our thirty-first Center of Progress is Göbekli Tepe, the site containing the oldest known monumental structures and perhaps the earliest archeological evidence of religious practice. While there is much disagreement on the origins of religion, many scholars describe Göbekli Tepe as the world’s first man-made temple, sanctuary, or holy place. Göbekli Tepe serves as a reminder of humanity’s capacity to create impressive structures as well as the long history of systems of faith and their profound influence on the world.

Göbekli Tepe lies in the southeast of what is today Turkey, about 30 miles from the border with Syria. Today, only a small portion of the prehistoric site of worship has been excavated, and much of it likely remains buried underground. Göbekli Tepe consists of large, ringed enclosures measuring as wide as 65 feet across, as well as rectangular pillar arrangements that may have once supported roofs. Each ring is made up of over 40 T-shaped stone pillars, some as tall as 18 feet. Another 250 or so pillars may remain buried. Some of the uncovered pillars are blank, but many feature detailed totem-like carvings depicting people, abstract symbols, and a wide variety of animals such as foxes, lions, bulls, scorpions, snakes, wild boars, birds, spiders, and insects. Some carvings appear to be part human and part animal and may represent deities. The pillars are the oldest known megaliths, predating the better-known Stonehenge by millennia.

Boardwalks now encircle the main excavation site, allowing tourists to view the pillars from different angles. And a roof has been constructed over the stones to protect the carvings and archeologists from the sweltering sun. In July, the average temperature in the area is over 100 degrees Fahrenheit. While the climate is only classified as semi-desert, rain almost never falls during the summer.

But if you could visit Göbekli Tepe in its heyday, you would encounter a very different world. The climate was wetter, and the surrounding environment was a vast grassland filled with wild goats and gazelles. Looking out over the endless fields, you would see tall grasses, such as einkorn, wheat, and barley, rippling in the wind. Rivers and waterfowl may have been visible as well. Your view of the surrounding plateaus would be excellent, as Göbekli Tepe stands on top of a hill. The name Göbekli Tepe, in fact, means “potbelly hill” in Turkish.

Radiocarbon dating suggests that the currently exposed structures of Göbekli Tepe were built over centuries, with some parts perhaps dating to 9500 BC and others constructed as recently as 8000 BC or even 7000 BC. It was a time of significant change. Communities like the ancient Natufians of Neolithic-era Jericho, located 500 miles southwest of Göbekli Tepe, were making the momentous transition from nomadic hunting and gathering to permanent settlement and agriculture. The people who built Göbekli Tepe were still mainly hunter-gatherers, but they also likely farmed in villages for at least part of the year. Archeological evidence shows that their diets consisted largely of meat but were supplemented by cereals that they probably farmed.

Erecting and carving humanity’s earliest monuments was a painstaking undertaking that required a multigenerational investment of time, labor, and craftsmanship. It likely involved hundreds of men. The people who built Göbekli Tepe did not yet have pottery or metal tools, nor the help of domesticated animals or wheeled vehicles. Flint tools would have been sufficient to carve the pillars, made of relatively soft limestone.

There is no proof that anyone ever lived at Göbekli Tepe, although some scholars believe it was nonetheless a settlement. There is much debate about whether the site offered sufficient access to water to sustain residents, and a lack of trash pit remnants suggests that people did not sleep at the site. Perhaps only a single person (such as a priest or shaman) or a small number of people resided there, leaving no archeological footprint that has yet been discovered. But even though Göbekli Tepe’s builders may have camped elsewhere, the site was certainly alive with activity. It may have been the closest thing to an urban center that the nomadic hunter-gatherers knew.

Turning away from the magnificent grasslands toward the imposing structures of Göbekli Tepe, one would have been struck by the aroma of freshly roasted wild boar, gazelle, red deer, and duck and witnessed the local hunter-gatherers commencing a festival amid their monuments. Researchers believe the hunter-gatherers congregated at the site to dance, celebrate, drink beer made from fermented grains, and dine together. In addition to food preparation tools, archeologists have so far uncovered some 650 carved stone platters and vessels at the site, some large enough to hold over 50 gallons of liquid. Over 100,000 bone fragments from wild game animals also suggest feasting. Such ritual feasts may have originated sometime between 8,000 BC and 6,000 BC, when the transition to agriculture linked the relative scarcity or abundance of food to certain seasons of the year. Among the festivities held at Göbekli Tepe may have been “work feasts” held throughout the site’s multigenerational construction to celebrate the completion of different sections of the temple.

From the Passover seders of Judaism to the Eid al-Fitr (nicknamed “Sugar Feast”) sweets of Islam, and from the Christmas dinners of Christianity to the staple deserts of Hinduism’s Diwali, religious feasts continue to hold great importance to communities across the world.

Much remains unknown about the nature of Göbekli Tepe and the religion that may have inspired its establishment. Prominent vulture carvings at the site have led some scholars to conclude that the religion was a “funerary cult” centered on venerating the dead. However, no human remains have been uncovered to suggest that Göbekli Tepe was ever a cemetery. Others think that the site was linked to astronomy and that its carvings reference constellations and comets. Some believe that Göbekli Tepe was a temple to the brightest star in Earth’s night sky, Sirius, because the central pillars may have framed the star as it rose. However, the main archeological team excavating the site rejects claims of an astronomical link.

Some scholars also think Göbekli Tepe may have been a holy site attracting hunter-gatherer visitors from across the Levant and as far away as Africa. Knowledge of the site would have traveled by word of mouth since writing did not exist yet. According to the journalist Charles Mann,

Göbekli Tepe may have been the destination for a religious pilgrimage, a monument for spiritual travelers to be awed by a religious experience—like the travel now made by pilgrims to the Vatican, Mecca, Jerusalem, Bodh Gaya (where Buddha was enlightened), or Cahokia (the enormous Native American complex near St. Louis).

Objects found at the site support this theory. Researchers have traced certain obsidian artifacts to volcanoes hundreds of miles away, and other tools found among the ruins exhibit carving styles suggesting far-flung origins such as the eastern Mediterranean. However, these objects could have also come to Göbekli Tepe via trade between different hunter-gatherer bands. Göbekli Tepe represented “a very cosmopolitan area … almost the nodal point of the Near East,” claims the historian Tristan Carter. “In theory, you could have people with different languages, very different cultures, coming together.”

At some point, the Neolithic people decided to bury Göbekli Tepe. Maybe their religion changed, and the site lost its relevance to them, or maybe the burial was itself a ritual tied to their particular spiritual beliefs. The site’s remarkable level of preservation is credited to the way in which it was buried. The hunter-gatherers then built another layer of stone pillars on top of the buried temple.

Religious faiths continue to provide a sense of meaning, structure, and inner peace to many people today—about 93 percent of people globally, to be precise. While the negative effects of violent strains of religious extremism are undeniable and religious conflict has caused much suffering, faith has also uplifted humanity in many ways.

In fact, religious inspiration is a common factor among several of the Centers of Progress. Some scholars think the religion of the ancient Indus Valley civilization may have been based around cleanliness, helping incentivize Mohenjo-Daro’s achievements in sanitation. In Baghdad, during that city’s Golden Age, the then-prevailing interpretation of Islam helped motivate scientific inquiry and the pursuit of knowledge. In Renaissance-era Florence, faith inspired many leading artists, and the Catholic Church funded groundbreaking artistic projects. During the Scottish Enlightenment that birthed modern social science, the dominant moderate branch of the Presbyterian Church embraced cutting-edge thinkers in Edinburgh. And later, prominent Anglican clergymen supported London’s trailblazing quest to end the global slave trade. In each of these cases, religion encouraged some manner of positive innovation.

That is not to downplay the harms that can arise from highly illiberal forms of religion. Examples include the restrictive interpretation of Islam that ultimately contributed to unraveling Baghdad’s status as a center of learning or the extremist Christian movement led by the radical friar Savonarola that sought to destroy Florence’s artworks.

Happily, liberty-minded thinkers can be found among the adherents of all major religions today. See, for example, the scholarship of Mustafa Akyol on the Muslim case for liberty, the writings of Stephanie Slade on the Catholic case for liberty, and the work of Aaron Ross Powell on the Buddhist case for liberty. Their writings illustrate how faith can champion the freedom needed to discover and create remarkable things.

While we may never learn why Göbekli Tepe was built, the site’s megalithic structures and intricate carvings arguably symbolize the power of religious devotion. The sophistication and artistic achievement embodied by this creation of a largely pre-agricultural society are astounding. If the site indeed served as a gathering place where prehistoric people worshiped now long-forgotten deities together, then it stands as a testament to the many ways in which humanity has sought to understand our place in the universe and express reverence. The mysterious, gigantic Stone Age site is worthy of being our thirty-first Center of Progress.