Before Cultural and Natural Wonders Earn UNESCO World Heritage Status, They Are Put on a ‘Tentative’ List. Here Are Five Nominees Worth Visiting Now

UNESCO’s World Heritage List started small, featuring just 12 inaugural sites back in 1978. Ranging from natural wonders, like Ecuador’s Galápagos Islands and the United States’ Yellowstone National Park, to manmade marvels, such as Germany’s Aachen Cathedral, these original spots were selected for their “outstanding value to humanity” from dozens of nominations from the 40 countries that had then signed the UNESCO World Heritage Convention, a pledge to protect our planet’s most important cultural and natural heritage.

Today, 194 countries and 12 territories have signed the convention, making them eligible to nominate sites for the World Heritage List, which now includes more than 1,248 locations, spread across the world. Each nominated site must meet at least one of ten criteria, such as boasting “superlative natural phenomena” or being a “masterpiece of human creative genius.” From there, the International Council on Monuments and Sites and the International Union for Conservation of Nature independently assess each nominee.

To earn World Heritage status, a site must first join the tentative list, which currently features 1,875 sites from 181 countries and territories. Manmade wonders—ancient forts, grand castles, rock art galleries—are listed alongside natural marvels, such as virgin rainforests, endangered reefs and national parks. UNESCO’s World Heritage Committee, which meets annually to choose a fresh batch of World Heritage Sites, provides a final evaluation.

“Inclusion on a tentative list does not guarantee that a site will eventually be nominated or inscribed on the World Heritage List,” a UNESCO spokesperson says. “Similarly, there is no standard timeframe between inclusion on a tentative list and nomination for inscription. Some sites are nominated within a few years, while others may remain on tentative lists for decades.”

Fun fact: New World Heritage Sites are being selected now

• The 48th session of the World Heritage Committee is taking place in Busan, South Korea, from July 19 to July 29, 2026. Over this time, 22 nominations to the World Heritage List will be examined.

World Heritage status boosts a location’s global fame and prestige, making it more alluring to visitors, says Jun Wen, an expert on tourism management at Macau University of Science and Technology in China. This typically prompts a major spike in tourism, he notes. “These [World Heritage] Sites stand to gain from UNESCO’s reputation, increasing their visibility as tourist destinations and also boosting the perceived reliability among prospective visitors,” Wen says.

But some locations are ill-prepared to cope with this tourism rush, says Jonathon Day, a sustainable tourism expert at Purdue University. “Even World Heritage Sites that work hard to manage tourism, such as Machu Picchu in Peru, must remain vigilant about visitor impacts,” he explains.

Peruachu Picchu by allowing no more than 5,600 daily visitors. Day does, however, emphasize that many World Heritage Sites would be heavily visited anyway, due to their beauty, and can benefit from UNESCO’s advice on site management

UNESCO recognizes that gaining World Heritage status can disrupt a site, and so it requires local authorities to submit a management plan, explains Greg Richards, a tourism expert at Tilburg University in the Netherlands. “However, the recent growth of what I have termed ‘mass cultural tourism’ in recent years means that issues of crowding are more prevalent these days,” Richards says.

Richards cites Vlkolinec, a photogenic village in Slovakia. Some of its residents recently told Euronews they’d be better off without the village’s UNESCO World Heritage listing. They claim to have lost privacy due to overtourism in this tiny community, revered for its well-preserved 1800s architecture and sublime location amid the mountains of central Slovakia.

UNESCO can add such sites to its separate list of World Heritage in Danger. This list consists of World Heritage Sites that have been damaged or are losing their authenticity due to various factors, including overtourism, pollution, natural disasters, armed conflict and irresponsible urban development. Currently, it features 53 endangered sites, from Everglades National Park in the United States to archaeological remains in Afghanistan and rainforests in Indonesia.

Meanwhile, here are five sites on the UNESCO World Heritage tentative list to visit now, while they remain lower in profile.

Sligo Passage Tombs, Ireland

Mysterious tunnels litter the wind-whipped peaks of County Sligo. Located about 125 miles northwest of Dublin, Sligo is a traditional region known for cinematic landscapes, old fashioned villages and a trove of prehistoric sites tied to Irish mythology.

The Sligo passage tombs are a cluster of more than 100 megalithic tombs, some up to 5,000 years old. Most of these burial chambers have never been excavated, creating uncertainty about whose remains they contain and why. From a distance they look like piles of rubble, but up close it becomes clear that the tombs are precise constructions, standing from a few feet to 35 feet tall.

Spread across an area of six square miles, the tombs are interconnected by subterranean passages, fueling speculation that they may have been intended as gateways to Tir Na Nog, Ireland’s mythical underworld of Celtic fairies and devils. It has long been rumored that this part of Ireland is pierced by underground passages that link with Oweynagat Cave, Ireland’s most famous “gate to hell.” During Samhain, the Irish pagan festival that later became Halloween, humans and supernatural creatures alike could supposedly use these tunnels to move between the living world and Tir Na Nog.

The Passage Tomb Landscape of County Sligo joined the UNESCO tentative list in 2023. Only a few of its tombs are known tourist sites, none more dramatic than that of Queen Maeve, which crests the 1,073-foot-tall Knocknarea mountain. This passage tomb is one of just a few in Sligo with a named occupant; according to Celtic mythology, Maeve was a warrior ruler of this part of Ireland. Archaeologists have never excavated her tomb, or similarly photogenic tombs atop the nearby hills of Keshcorran and Carrowkeel.

Both Keshcorran and Carrowkeel are well-preserved archaeological sites and free for tourists to visit. After walking 10 to 20 minutes from each location’s parking lot, visitors can run their hands along these timeworn tombs while absorbing wide vistas of Sligo’s rolling farmland.

Cape York Peninsula, Australia

Australia’s northernmost region is decorated by 20,000-year-old rock art depicting the mythology of Indigenous Australians, one of the world’s oldest continuous civilizations. A wild expanse of rainforest, wetlands and savanna in the state of Queensland, Cape York Peninsula covers more than 45,000 square miles, the same size as Pennsylvania.

Despite its vastness, the peninsula is home to only 17,000 people—more than half of whom are Indigenous Australians. Humans have inhabited Cape York for up to 37,000 years, and their deep history and lore is etched into this landscape. Rock art galleries across the peninsula, especially in Quinkan Country, depict humans, birds, fish, reptiles, dingoes, echidnas, Indigenous rituals and ancestral beings.

According to Indigenous lore, those latter, supernatural entities created our planet and gave Australia’s Indigenous people the customs, codes of conduct and mythology that still prevail. They also spawned Cape York’s sublime geographic features—boulder fields, dune systems, coastal salt flats, mangrove forests—all of which are key elements of the site, which has been on the UNESCO tentative list since 2024.

Last year, Australia’s biggest rock art site, Murujuga, a group of more than one million petroglyphs by Indigenous communities in remote Western Australia, earned World Heritage status. Soon, Cape York Peninsula could join it.

An official designation may convince more tourists to seek out this remote wonder. Cape York Peninsula begins about 100 miles north of the nearest city, Cairns, where travelers can rent a car to drive into the wilderness or fly to one of several small Cape York communities, including Bamaga, at its very tip.

The Ringed Seal Archipelagos of Lake Saimaa, Finland

Fewer than 550 Saimaa ringed seals remain on Earth, with all of these endangered animals residing in Lake Saimaa, Finland’s largest lake. The population plummeted in the 1900s. But, thanks to conservation efforts, the species has now recovered so well that tourists can join boat tours to see these seals basking by the lake’s edge—an especially common sight during the warmer months of May and June.

Saimaa ringed seals are a rare subspecies of seals that are landlocked, due to their unique history. Some 9,500 years ago, after geological forces gradually disconnected Lake Saimaa from the Baltic Sea, these seals were left isolated in this body of freshwater. Since then, they’ve evolved to behave in ways that differ from most other seals. They are far more solitary, and yet they are the only type of seal that breeds and lives near human communities. Lake Saimaa is fringed by five small cities, including its main tourist hub, Savonlinna, which boasts a 15th-century castle and an array of hotels, bars and restaurants.

Lake Saimaa itself is extraordinary. Located in southeastern Finland, it is 112 miles long, 87 miles wide, dotted by about 14,000 islands, pierced by dozens of narrow straits and surrounded by sheltered bays perfect for ringed seal breeding.

While Lake Saimaa is sheeted by ice from December to April, tourists can kayak, fish, hike, swim and cycle its leafy fringes the rest of the year. Most tourists reach Savonlinna from the Finnish capital, Helsinki, which is about 155 miles to the southwest. They either fly, catch a train or bus, or rent a car to complete the four-hour drive.

Real Felipe Fortress of Callao, Peru

Peru’s magnificent Real Felipe Fortress of Callao was originally erected in 1542 as the regional headquarters of the occupying Spanish, who controlled swaths of Central and South America until the 1820s. Peru was Spain’s most valuable territory, so the Spanish built a commanding seaside fortification at the port of Callao, ten miles west of Lima, the capital.

That initial structure was one of thousands of buildings demolished in 1746 by an earthquake and subsequent tsunami, which also claimed more than 1,000 lives. It was rebuilt in the 1770s as a huge, pentagonal fort ringed by a moat, guarded by five bastions and surrounded by an outer stone wall measuring almost a mile long.

While the fort still holds functioning military structures, tourists can wander many parts of its 24-acre grounds. Two on-site museums exhibit military artifacts and explain the fort’s history. The complex was embroiled in Peru’s long fight for freedom from Spain, whose control of Peru, and the region more widely, effectively ended in 1826, when the Spanish surrendered this fortress. Nowadays, visitors to Callao can use its elevated perch to peer out at the same seas where Spanish ships once retreated over the horizon, leaving Peru independent once more.

Gcwihaba Caves, Botswana

Horst Klemm/Greatstock/Alamy

The flat expanse of the Kalahari Desert stretches on and on across Botswana, until broken by dolomite hills along the Namibian border, in a remote, sparsely inhabited part of southern Africa. Burrowed into these peaks, known as the Aha Hills, are six unusual cave systems with memorable fossils and rock formations.

The Gcwihaba Caves are more than two million years old. They were little known until 1992, when researchers entered the caves and found fossilized bones as well as an impressive array of stalagmites, stalactites, helictites, flowstones and cave pearls. UNESCO describes its cave fossil deposits as “possibly the richest in southern Africa.”

Tourists can now cautiously explore Gcwihaba Caves, too. From Botswana’s capital, Gaborone, it is a slow, 630-mile journey, which requires a four-wheel-drive vehicle due to rough roads. Visitors can then stay at campsites near the caves.

Upon entering the caves, visitors must remain calm in a dark, eerie environment teeming with thousands of bats. Parts of this sprawling subterranean system are too cramped for humans, while other caverns soar up to 33 feet high.

Visitors can also hike through the surrounding hilly environment. Keen-eyed tourists may spot the rare Namaqua fig trees, which are special to this area, as well as barking geckos, tent tortoises and Rüppell’s parrots, though their vision can never match that of the barn owls inhabiting these remarkable caves.

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