Djulfa, a sacred site for Armenian Christians, is disqualified from consideration because the host of this year’s UNESCO World Heritage Committee session, the government of Azerbaijan, has erased its existence and destroyed tens of thousands of Armenian cultural monuments.

Moments ago, the global organization for cultural preservation — UNESCO — announced the final list of 29 historical and natural wonders that have now officially joined the ranks of the Pyramids and Grand Canyon as World Heritage Sites. But the celebrated site of Djulfa, which boasted the world’s largest collection of exquisitely-carved medieval cross-stones as remnants of the area’s once-thriving community of Armenian Christians, was not among the 35 candidates vying for World Heritage Site designation. The legendary historical site is disqualified from such an honor, because the host of this year’s UNESCO World Heritage Committee session, the government of Azerbaijan, has erased its existence.

In December 2005, Nshan Topouzian, the leader of north Iran’s Armenian church, posted a chilling video online. An Iranian border patrol had alerted him to the deployment of Azerbaijani troops at Iran’s border with Azerbaijan, where Djulfa had stood for centuries. The tearful Bishop rushed to videotape over 100 Azerbaijani soldiers armed with sledgehammers, dump trucks, and cranes as they destroyed the sacred site, pounding the intricately carved sacred medieval headstones into rubble and then dumping their pulverized remains into the river. Within weeks, thousands of sacred stones, which had memorialized numerous medieval Armenian merchants — a community whose legacies include Europe’s first cafés and Captain Kidd’s pirated loot — had disappeared. This erasure is part of a state-sanctioned war on history that is arguably the worst act of cultural cleansing of the 21st-century. Yet unlike the cultural crimes of ISIS or the Taliban, few have heard of it.

As Sarah Pickman and I exposed in an investigative report in February, Azerbaijan’s destruction of Djulfa was the grand finale in a broader campaign. Between 1997 and 2006, the authoritarian regime in Azerbaijan worked systematically to demolish every trace of medieval Armenian Christianity in the region called Nakhichevan (formally called the Nakhchivan Autonomous Republic). The final toll included 89 medieval churches, 5,840 cross-stones — half of which were at Djulfa, and 22,000 tombstones. One of the churches erased was the majestic Saint Thomas cathedral of Agulis, originally founded as a chapel in the 1st century and one of the oldest churches in the world. According to official Azerbaijan, none of these 28,000 monuments were destroyed: they never existed to begin with.

As the preeminent organization charged with protecting global heritage, UNESCO was expected to speak out to prevent Azerbaijan’s erasure of Nakhichevan’s Armenian past. Instead, UNESCO has not only avoided a public condemnation of this destruction but also praised Azerbaijan as a “land of tolerance.” The cooperation between UNESCO and Azerbaijan became strong in 2013 after the latter donated $5 million to the cash-strapped organization. In 2011, after Washington cut a quarter of UNESCO’s budget due to member states’s vote in favor of Palestinian membership, the organization had to seek alternative funding.

Undoubtedly, UNESCO conducts vital operations across the world. Its different arms oversee the designation of cultural and natural World Heritage Sites, educate children, empower women, and serve vulnerable communities around the globe. The 1970 Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property, an important international treaty, is one of many lasting legacies of the organization.

Underfunded international organizations cannot be too picky about their donors. Resourceful countries with questionable motives know this all too well, which is why Azerbaijan has made its courting of UNESCO a top foreign policy priority. An exiled Azerbaijani dissident historian, Arif Yunus, thinks that his government’s obsession with receiving UNESCO’s approval has more to do with domestic than international politics. “Nothing projects the Aliyev dictatorship’s power to Azerbaijani dissidents,” Yunus told me last year, “like committing cultural genocide in Nakhichevan then showering in international praises of tolerance.”

But others explain the destruction through the lens of ethnic conflict. Following the USSR’s sudden dissolution in 1991, Djulfa — along with the wider Nakhichevan region — became an exclave of independent Azerbaijan. By then, Nakhichevan’s indigenous Armenian population had dwindled to zero. This fate was precisely what the Armenian-majority population of another autonomy within Soviet Azerbaijan, Nagorno-Karabakh, had wished to avoid by seeking independence. That led to the early 1990s Armenian-Azerbaijani war, which Azerbaijan lost.

Having lost territories and amassed refugees, Azerbaijan’s narrative blames every problem and criticism alike on “Armenian occupiers.” According to official Azerbaijan, Armenians’s latest plot is fabricating destruction of imaginary monuments for the purpose of laying new territorial claims. “Absolutely false” fabrication by “the Armenian lobby.” That is how, in April 2006, Azerbaijan’s president berated a confirmation of Djulfa’s destruction by a now-exiled journalist. Another dissident, the famous Azerbaijani novelist Akram Aylisli, has been under house arrest in Baku since 2013 for the crime of authoring Stone Dreams, a novel that pays homage to the vanished Armenian past of Aylisli’s native Nakhichevan.

Whether UNESCO should altogether sever its ties with an oil-rich country that destroyed 28,000 cultural monuments may be up for debate. But hosting the world’s top preservation summit in that country crosses a red line. The cruel irony of UNESCO hosting the World Heritage Committee session in Azerbaijan this week is nothing short of an insult to all world heritage.