Hikers from the cablecar near the smoking summit of 3350m volcano Mount Etna during an active phase, Mount Etna, UNESCO World Heritage Site, Sicily, Italy, Mediterranean, Europe

Buildings in steep gorge at Modica, a town famed for Sicilian Baroque architecture, UNESCO World Heritage Site, Modica, Ragusa Province, Sicily, Italy, Mediterranean, Europe

Ash, rock and sulphur at the smoking summit of 3350m high volcano Mount Etna during an active phase, Mount Etna, UNESCO World Heritage Site, Sicily, Italy, Mediterranean, Europe

The 17th century Cathedral, collapsed in 1996 and rebuilt, at Noto, famed for Baroque architecture, UNESCO World Heritage Site, Noto, Sicily, Italy, Mediterranean, Europe

The 17th century Cathedral, collapsed in 1996 and rebuilt, at Noto, famed for Baroque architecture, UNESCO World Heritage Site, Noto, Sicily, Italy, Mediterranean, Europe

Panoramic photo of Megalithic stone circle, Avebury, UNESCO World Heritage Site, Wiltshire, England. United Kingdom, Europe

Glaciar Perito Moreno (Perito Moreno Glacier), Lago Argentino, Los Glaciares National Park, UNESCO World Heritage Site, Patagonia, Argentina, South America

Glaciar Perito Moreno (Perito Moreno Glacier), Lago Argentino, Los Glaciares National Park, UNESCO World Heritage Site, Patagonia, Argentina, South America

Cerro Torre, granite spire 1400 metres tall, Los Glaciares National Park, UNESCO World Heritage Site, Patagonia, Argentina, South America

Glaciar Perito Moreno (Perito Moreno Glacier), Lago Argentino, Los Glaciares National Park, UNESCO World Heritage Site, Patagonia, Argentina, South America

Glaciar Perito Moreno (Perito Moreno Glacier), Lago Argentino, Los Glaciares National Park, UNESCO World Heritage Site, Patagonia, Argentina, South America

Huge stone walls the fortress of Suwon, UNESCO World Heritage Site, South Korea, Asia

Huge stone walls around the fortress of Suwon, UNESCO World Heritage Site, South Korea, Asia

Huge stone walls around the fortress of Suwon, UNESCO World Heritage Site, South Korea, Asia

Cheomseongdae, oldest astronomical observatory in east Asia, Gyeongju, UNESCO World Heritage Site, South Korea, Asia

Ilchulbong tuff cone, Sunrise Peak, island of Jejudo, UNESCO World Heritage Site, South Korea, Asia

The 19th century Russian Orthodox Alexander Nevsky Cathedral on Toompea, Old Town, UNESCO World Heritage Site,Tallinn, Estonia, Baltic States, Europe

Looking east from Holbank Crags showing course of the Roman wall past Housesteads Wood to Sewingshields Crag, Hadrian's Wall, UNESCO World Heritage Site, Northumbria (Northumberland), England, United Kingdom, Europe

Traditional colorful houses, Valparaiso, UNESCO World Heritage Site, Chile, South America

Pena National Palace, built in 1840s for the Royal family, UNESCO World Heritage Site, Sintra, Portugal, Europe

Looking west from Kings Hill to Housesteads Crag, Cuddy and Hotbank Crags, Hadrians Wall, UNESCO World Heritage Site, Northumberland (Northumbria), England, United Kingdom, Europe

Looking west from Kings Hill to Housesteads Roman Fort and crag, Cuddy and Hotbank Crags, Hadrians Wall, UNESCO World Heritage Site, Northumberland (Northumbria), England, United Kingdom, Europe

Vernazza village and harbour at dusk, Cinque Terre, UNESCO World Heritage Site, Liguria, Italy, Europe

Giant's Causeway, UNESCO World Heritage Site, Causeway Coast, Antrim, Ulster, Northern Ireland, United Kingdom, Europe

Horse Carriage, Palacio de la Artesania (Palace of the Artisans), Old Town, UNESCO World Heritage Site, Havana, Cuba, West Indies, Caribbean, Central America

Clock Tower (Turnul cu Ceas) at dusk, Sighisoara, UNESCO World Heritage Site, Mures County, Transylvania Region, Romania, Europe

Yangdong folk village, UNESCO World Heritage Site, Gyeongsangbuk-do, South Korea, Asia

Manjanggul Lava Tube, UNESCO World Heritage Site, Jeju Island, South Korea, Asia

National Congress, UNESCO World Heritage Site, Brasilia, Federal District, Brazil, South America

Angel sculptures, Alfredo Ceschiatti, Metropolitan Cathedral, UNESCO World Heritage Site, Brasilia, Federal District, Brazil, South America

Metropolitan Cathedral, UNESCO World Heritage Site, Brasilia, Federal District, Brazil, South America

National Library, skyscrapers, dusk, UNESCO World Heritage Site, Brasilia, Federal District, Brazil, South America

Bison (Bison bison), Hayden Valley, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Yangdong folk village, UNESCO World Heritage Site, Gyeongsangbuk-do, South Korea, Asia

Bare trees surrounding the banks of Holme Fell Tarn on an overcast winters day in the Lake District National Park, UNESCO World Heritage Site, Cumbria, England, United Kingdom, Europe

Old Fortress, Kerkyra city, UNESCO World Heritage Site, Corfu, Ionian Islands, Greek Islands, Greece, Europe

Royal Tombs burial mounds at sunrise, UNESCO World Heritage Site, Gyeongju, Gyeongsangbuk-do, South Korea, Asia

Durdle Door, Jurassic Coast, UNESCO World Heritage Site, Dorset, England, United Kingdom, Europe

Agios Spyridon church, Kerkyra City, UNESCO World Heritage Site, Corfu, Ionian Islands, Greek Islands, Greece, Europe

Market square and the Belfry, Historic center of Bruges, UNESCO World Heritage Site, Belgium, Europe

Houses along a channel, Historic center of Bruges, UNESCO World Heritage Site, Belgium, Europe

Belfry at twilight, Historic center of Bruges, UNESCO World Heritage Site, Belgium, Europe

Provincial Government building, Market Square, Historic center of Bruges, UNESCO World Heritage Site, Belgium, Europe

Gruuthuse Museum, Historic center of Bruges, UNESCO World Heritage Site, Belgium, Europe

Old Saint John Hospital, Historic center of Bruges, UNESCO World Heritage Site, Belgium, Europe

Historium Museum, Market square, Historic center of Bruges, UNESCO World Heritage Site, Belgium, Europe

Dry stone wall and grazing sheep, Lake District National Park, UNESCO World Heritage Site, Cumbria, England, United Kingdom, Europe

A calm clear autumn morning at Elterwater as the first light of a new day illuminates the trees and mist, Lake District National Park, UNESCO World Heritage Site, Cumbria, England, United Kingdom, Europe

Mount Ngauruhoe, 2287m, on the Tongariro Crossing, in the oldest national park in New Zealand, Tongariro National Park, UNESCO World Heritage Site, Taupo, North Island, New Zealand, Pacific

Hikers walking towards Barn Bluff on the overland track in Cradle Mountain Lake St. Clair National Park, part of Tasmanian Wilderness, UNESCO World Heritage Site, Tasmania, Australia, Pacific

Reclining Buddha, Royal Rock Temple, Golden Temple of Dambulla, UNESCO World Heritage Site, Dambulla, Sri Lanka, Asia

Wall carving of Buddhist icon, Temple of the Sacred Tooth Relic, UNESCO World Heritage Site, Kandy, Sri Lanka, Asia

Morning Glory Pool and surrounds, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Golden sitting Buddhist statue, Temple of the Sacred Tooth Relic, UNESCO World Heritage Site, Kandy, Sri Lanka, Asia

Colourful Buddhist flags adorning columns, Temple of the Sacred Tooth Relic, UNESCO World Heritage Site, Kandy, Sri Lanka, Asia

Vertical columns, The Kiri Vihara Buddhist temple ruins, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Seated Buddha, Gal Vihara, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Temple of the Sacred Tooth Relic, UNESCO World Heritage Site, Kandy, Sri Lanka, Asia

Entrance to Dambulla Museum with caves beyond, Dambulla, Sri Lanka, Asia

Sigiriya (Lion Rock) frescoes or ancient wall paintings, UNESCO World Heritage Site, Sri Lanka, Asia

Sigiriya (Lion Rock) frescoes or ancient wall paintings, UNESCO World Heritage Site, Sri Lanka, Asia

Sitting Buddha statues, Royal Rock Temple, Golden Temple of Dambulla, UNESCO World Heritage Site, Dambulla, Sri Lanka, Asia

Sigiriya (Lion Rock), UNESCO World Heritage Site, Sri Lanka, Asia

Two seated Buddha statues, Royal Rock Temple, Golden Temple of Dambulla, UNESCO World Heritage Site, Dambulla, Sri Lanka, Asia

Reclining Buddha, Gal Vihara, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

A monk sits and looks at his phone beneath shelter, Royal Rock Temple, Golden Temple of Dambulla, UNESCO World Heritage Site, Dambulla, Sri Lanka, Asia

The stone columns of the open air Audience Hall, Temple of the Sacred Tooth Relic, UNESCO World Heritage Site, Kandy, Sri Lanka, Asia

Entrance to Dambulla Museum with caves beyond, Dambulla, Sri Lanka, Asia

Sigiriya (Lion Rock) frescoes or ancient wall paintings, UNESCO World Heritage Site, Sri Lanka, Asia

Bathing Pool (Nekum Pokuna), Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Statue of sitting Buddha, Temple of the Sacred Tooth Relic, Kandy, UNESCO World Heritage Site, Sri Lanka, Asia

Rankot Vihara dagoba (Stupa) Buddhist temple ruins, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Sitting and reclining Buddha statues, Royal Rock Temple, Golden Temple of Dambulla, UNESCO World Heritage Site, Dambulla, Sri Lanka, Asia

Entrance to Kiri Vihara Buddhist temple ruins with moonstone at entrance, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Vatadage ancient ruins, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Sigiriya (Lion Rock) frescoes or ancient wall paintings, UNESCO World Heritage Site, Sri Lanka, Asia

Reclining Buddha, Gal Vihara, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Wall and ceiling murals inside the Temple of the Sacred Tooth Relic, Kandy, Sri Lanka

The Kiri Vihara Buddhist temple ruins, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Vertical columns, the Kiri Vihara Buddhist temple ruins, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

A dome shaped structure in the Kiri Vihara Buddhist temple ruins, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Golden sitting Buddhist statue, Temple of the Sacred Tooth Relic, UNESCO World Heritage Site, Kandy, Sri Lanka, Asia

Satmahal Prasada, Quadrangle, Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Statue of reclining Buddha, Royal Rock Temple, Golden Temple of Dambulla, UNESCO World Heritage Site, Dambulla, Sri Lanka, Asia

Cold tourists on seat surrounded by steam, Upper Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Charles Bridge, UNESCO World Heritage Site, Prague, Czech Republic, Europe

Dead trees and steam with mountain backdrop and blue skies, Mammoth Hot Springs, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Standing Buddha statue in Atadage building in the Quadrangle, ancient city of Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Notice at Gal Viharaya, ancient city of Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Bathing pool in rock palace fortress on rock summit, Sigiriya, UNESCO World Heritage Site, Central Province, Sri Lanka, Asia

Buildings of rock palace fortress on rock summit, Sigiriya, UNESCO World Heritage Site, Central Province, Sri Lanka, Asia

Metal staircase climbing to rock palace fortress, Sigiriya, UNESCO World Heritage Site, Central Province, Sri Lanka, Asia

Bathing pool in rock palace fortress on rock summit, Sigiriya, UNESCO World Heritage Site, Central Province, Sri Lanka, Asia

Parakramabahu statue site, ancient city of Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Stone carving figures, Lankatilaka building, Alahana Pirivena complex, ancient city of Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Pabula Vihara temple, ancient city of Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Seated Buddha in Vatadage building, The Quadrangle, ancient city of Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

The Lotus Mandapa building, The Quadrangle, ancient city of Polonnaruwa, UNESCO World Heritage Site, Sri Lanka, Asia

Fallen lodgepole pines, Grand Prismatic Spring, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

Fishing Cone Geyser with freezing mists, Yellowstone Lake at West Thumb Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America