Witness circumhorizontal arc in the sky, a rare optical phenomenon caused by ice crystals
Witness white rainbow in foggy conditions, a rare optical phenomenon similar to a rainbow
View pouch-like cloud formations that often appear before severe storms
Catch rare green flash as sun sets over ocean horizon, a brief optical phenomenon
See the Kawah Ijen volcano in Indonesia, famous for its blue flames and turquoise crater lake
Witness rare natural electrical phenomenon that appears as glowing spheres during thunderstorms
Witness lightning generated within volcanic eruption plumes
View naturally multicolored tree bark that reveals bright colors as it sheds
Witness upper atmospheric lightning that occurs above thunderstorm clouds
Witness rare desert wildflower blooms that occur after rainfall in locations like Chile's Atacama Desert or California's Death Valley
Watch rare tubular cloud formations that can stretch for hundreds of kilometers, notably visible in Australia's Gulf of Carpentaria
One of the world's largest wetlands.
Africa's second-greatest antelope migration.
Boardwalk to nesting wandering albatrosses — the largest wingspan of any bird — on a tiny island in the Bay of Isles.
Giant otters on the Rupununi river.
West Africa's last wild giraffes.
Aldabra giant tortoises roam free on Curieuse and La Digue — some over 150 years old.
The only hippos on Earth that swim in the sea, wallowing in lagoons and grazing the beaches of Orango Island.
Palm forest of the coco de mer, UNESCO-listed.
Spot lemurs in the Andasibe rainforest.
Ten million fruit bats darken the sky each November — the world’s largest mammal migration.
Djibouti’s only forest, a relic juniper woodland on the Goda mountains with the endemic Djibouti francolin.
The "river of five colours", turned red by aquatic plants between June and November.
Track down the world’s largest flower blooming on the rainforest floor.
Remote geyser basin on the volcanic Kamchatka peninsula, reachable only by helicopter.
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