Great Blue Hole, an underwater cave in the Belize Barrier Reef Reserve System
Great Blue Hole, an underwater cave in the Belize Barrier Reef Reserve System (Photo: Wollertz/Shutterstock)

At least 54 of 206 natural World Heritage Sites heritage sites are grappling with serious threats from development and industry, according to UNESCO.

A report from the World Wildlife Fund in 2016 puts the number even higher, saying almost half of all natural heritage sites are under threats from "oil and gas exploration and extraction, mining, illegal logging, construction of large-scale infrastructure, overfishing and unsustainable water use."

Since its adoption in 1972 by the United Nations, the World Heritage Site program has honored more than 1,070 places around the world for their natural, cultural and mixed significance. Celebrating these wonders is only part of it, however — the designation is also meant to garner international attention for sites that are struggling.

"The challenges to World Heritage conservation, combined with the effects of climate change, are unprecedented in human history," according to the UNESCO statement addressing the WWF survey. "The need for joint and collective collaboration among all stakeholders has never been more important."

One site that's grappling with these man-made forces of destruction is the Belize Barrier Reef Reserve System.

This outstanding marine landscape, designated as a World Heritage Site in 1996, boasts not only the largest barrier reef in the Northern Hemisphere, but also a series of thick mangrove forests, coastal lagoons, sand cays and atolls. One of the most outstanding sights within the reef system is a 405-foot deep submarine sinkhole known as the Great Blue Hole (pictured above).

Sadly, the reef remains extremely vulnerable to oceanic pollution and the consequences of under-regulated tourism, shipping and fishing. Scientists have found that more than 40 percent of the 185-mile stretch of reef has suffered serious damage since 1998. Despite encouraging actions by the government to ban bottom trawling and offshore oil drilling, rising ocean temperatures and hurricanes — both triggered by global climate change — are also responsible for the degradation and mass bleaching of the reef's coral.

Because of these factors, the Belize Barrier Reef Reserve System was placed on UNESCO's List of World Heritage in Danger, which was established as a way to promote global awareness and facilitate solutions to the problems the affected sites face.

There are a total of 54 sites included on the list as of October 2017, but that number is always changing. While many of the sites are so endangered that they must stay on the list in virtual perpetuity, other sites have solutions at hand. In other cases, as with the Everglades in southern Florida, the site may be added and taken off the list, only to be added back again a few years later.

Continue below to learn about more endangered World Heritage Sites, both natural and cultural, that could use a helping hand in restoring and preserving their integrity:

Chan Chan Archaeological Zone — La Libertad, Peru

Chan Chan Archaeological Zone in La Libertad, Peru
Chan Chan Archaeological Zone in La Libertad, Peru (Photo: mikluha_maklai/Shutterstock)

Date of Inscription: 1986
Endangered: 1986-present

Why it's important: Built along the northwestern coast of Peru in 850 A.D., Chan Chan was once the bustling capital of the Chimú Kingdom before succumbing to Incan control in the 15th century. According to UNESCO, "the planning of this huge city, the largest in pre-Columbian America, reflects a strict political and social strategy, marked by the city's division into nine 'citadels' or 'palaces' forming autonomous units."

Why it's threatened: Constructed of sedimentary earthen material, the city is extremely prone to erosion and deterioration. This is especially true in years marked by El Niño. Additionally, illegal farming practices surrounding the site as well as encroaching urban development are a constant danger to the integrity of the archaeological zone.

Ancient City of Damascus — Syria

The Great Mosque of Damascus, Syria.
The Great Mosque of Damascus, Syria. (Photo: Erdal Akan/Shutterstock)

Date of inscription: 1979
Endangered: 2013-present

Why it's important: It's literally the oldest city in the world.

Why it's threatened: In the midst of mortar shelling and bombings stemming from the Syrian Civil War, Damascus was officially labeled as endangered in 2013 alongside several other important Syrian heritage sites.

Virunga National Park — Democratic Republic of the Congo

A baby gorilla at Virunga National Park in the Democratic Republic of the Congo.
A baby gorilla at Virunga National Park in the Democratic Republic of the Congo. (Photo: LMspencer/Shutterstock)

Date of inscription: 1979
Endangered: 1994-present

Why it's important: As Africa's first national park, Virunga is celebrated for its gorgeous diversity of habitats and plethora of endemic species, most notably the rare mountain gorilla.

Why it's threatened: Virunga was listed as endangered in 1994 following the end of the Rwandan civil war. The subsequent influx of refugees and isolated armed groups into the area has continued to cause widespread deforestation and poaching over the last two decades.

Portobelo-San Lorenzo fortifications — Panama

The ruins of Fort San Lorenzo at Portobelo, Panama.
The ruins of Fort San Lorenzo at Portobelo, Panama. (Photo: Rob Crandall/Shutterstock)

Date of inscription: 1980
Endangered: 2012-present

Why it's important: Found along the Caribbean side of Panama, these fascinating ruins are priceless examples of 17th- and 18th-century Spanish military architecture. UNESCO explains that this Panamanian historic compound "is a key element to the understanding of the adaptation of European building models and their impact on the New World transformation during the modern era."

Why it's threatened: The fortifications were listed as endangered in 2012 due to an unfortunate lack of maintenance that is allowing the elements to wreak havoc on the site.

Timbuktu — Mali

Mopti Mosque in Timbuktu, Mali.
Mopti Mosque in Timbuktu, Mali. (Photo: Marianoblanco/Shutterstock)

Date of inscription: 1988
Endangered: 1990-2005, 2012-present

Why it's important: Situated within the historic city center of Timbuktu, the three mosques and 16 mausoleums that make up this World Heritage Site were designated because of their religious and architectural significance as one of Africa's earliest Islamic holy places.

Why it's threatened: The Timbuktu site has been listed as endangered throughout most of its history as a World Heritage Site due to the ongoing threat of desertification. In 2012, it faced yet another issue: Threats of deliberate destruction by radical Islamist groups like Al-Qaeda, Ansar Dine and Boko Haram, who believe the shrines and mausoleums are examples of idoltry.

Everglades National Park — Florida, U.S.

A majestic heron swoops over the wetlands of Everglades National Park at sunrise.
A majestic heron swoops over the wetlands of Everglades National Park at sunrise. (Photo: Brian Lasenby/Shutterstock)

Date of inscription: 1979
Endangered: 1993-2007, 2010-present

Why it's important: Often called the "river of grass," the Everglades lays claim to being one of the most important wetland ecosystems in North America. Situated along the southern tip of the Florida peninsula, this national park serves as a vital sanctuary for many wetland birds as well as an array of other endangered wildlife, including manatees, crocodiles and panthers.

Why it's threatened: The Everglades has suffered extensive, long-term damage due to decades of widespread agricultural and urban development throughout much of its watershed. The subsequent deterioration of the ecosystem's water quality and flow has resulted in the tragic loss of vital marine habitats and a decline in the species that make it their home. This is compounded by the damages wrought by natural disasters, including 1993's Hurricane Andrew.

Bamiyan Valley — Bamyan, Afghanistan

Cultural Landscape and Archaeological Remains of the Bamiyan Valley in Bamyan, Afghanistan.
Cultural Landscape and Archaeological Remains of the Bamiyan Valley in Bamyan, Afghanistan. (Photo: Tor Pur/Shutterstock)

Date of inscription: 2003
Endangered: 2003-present

Why it's important: This beautiful valley was once the site of the "Buddhas of Bamiyan" — two massive 6th century statues that were deliberately destroyed in 2001 by the Taliban, who called them "idols." In the wake of this tragic destruction, the artistic and architectural legacy of the buddhas and their remaining alcoves were established as a World Heritage Site in hopes of preserving (and possibly rebuilding) what little is left of the statues.

Why it's threatened: The buddhas may have been destroyed, but that doesn't mean the fight to preserve their archaeological significance is over. There has been talk of rebuilding the statues, but until something concrete happens, the landscape remains mired in a state of virtual neglect and illicit misuse.

Land of Olives and Vines — Battir, Palestine

The ancient terrace system of Battir, Palestine.
The ancient terrace system of Battir, Palestine. (Photo: idobi/Wikimedia)

Date of inscription: 2014
Endangered: 2014-present

Why it's important: Battir possesses one of the oldest and most sophisticated terraced irrigation systems in the world. According to UNESCO, "The water distribution system used by the families of Battir is a testament to an ancient egalitarian distribution system that delivers water to the terraced agricultural land based on a simple mathematical calculation and a clear time-managed rotation scheme."

Why it's threatened: Several attempts by the Israeli government to erect a separation wall in the middle of Battir would effectively destroy not only the aesthetics of the ancient landscape but also the functionality of the terraced water systems that the people in the community continue to rely on.

Coro and its Port — Falcón, Venezuela

Coro and its Port of Falcón, Venezuela
Coro and its Port of Falcón, Venezuela (Photo: Rafal Cichawa/Shutterstock)

Date of inscription: 1993
Endangered: 2005-present

Why it's important: Founded in 1527, this intensely historic colonial-era town boasts as many as 602 historic buildings. According to UNESCO, "Coro is the only surviving example of a rich fusion of local traditions with Spanish Mudéjar and Dutch architectural techniques."

Why it's threatened: Major storm damage to the site between November 2004 and February 2005 prompted its inclusion into the endangered list. Additionally, the site has become to the subject of "inappropriate development [...] due to the lack of urban controls [and] a regulated buffer zone." These developments, which include a new monument, a city entrance gate and a beach walkway, may negatively impact the value and integrity of the historic area.

Editor's note: This story has been updated since it was originally published in April 2016.

Catie Leary ( @catieleary ) writes about science, travel, animals and the arts.