Walkway leading into the Big Room, Carlsbad Caverns, New Mexico (© Doug Meek/Getty Images)

Hawaiian lei flower garlands (© Jotika Pun/Shutterstock)

Blue Dragon Lava Flow, Craters of the Moon National Monument, Idaho (© Alan Majchrowicz/Getty Images)

Brittlebushes blooming in springtime, Sonoran Desert, Arizona (© Charles Harker/Getty Images)

Ruins of an ancient monastery on the island of Skellig Michael, Ireland (© MNStudio/Getty Images)

Colonnade in San Miguel de Allende, Guanajuato, Mexico (© Mint Images/Getty Images)

The Roaches, Peak District, England (© George W Johnson/Getty Images)

A duckling swimming in a water meadow, Suffolk, England (© Nick Hurst/Getty Images)

View of Château d'If in the port of Marseille, France (© Sergii Figurnyi/Alamy)

Tulips at Emirgan Park in Istanbul, Türkiye (© Ozbalci/Getty Images)

Misool, Raja Ampat Islands, Indonesia (© Giordano Cipriani/Getty Images)

An indigo bunting perched on a branch, Texas (© Jeff R Clow/Getty Images)

Guanaco mother and newborn baby in grassland, La Pampa Province, Argentina (© Gabriel Rojo/Minden Pictures)

Fish River Canyon, Namibia (© R. M. Nunes/Getty Images)

The Blue City of Jodhpur, India (© cinoby/Getty Images)

'Feelings are Facts,' by artist Olafur Eliasson and architect Ma Yansong, Beijing, China (© Feng Li/Getty Images News)

A family of African elephants in Tarangire National Park, Tanzania (© Vicki Jauron, Babylon and Beyond Photography/Getty Images)

Blue whale skeleton in the Natural History Museum, London, England (© Bailey-Cooper Photography/Alamy)

Village of Vernazza, Cinque Terre, Liguria, Italy (© Roberto Moiola/Sysaworld/Getty Images)

Bee tending a honeycomb (© Simun Ascic/Alamy)

Cameron Highlands tea plantation, Malaysia (© alex cheong/Getty Images)

Tasmanian snow gum trees, Mount Field National Park, Tasmania, Australia (© Ignacio Palacios/Getty Images)

Indian star tortoise, Sri Lanka (© Robin Chittenden/Minden Pictures)

Añisclo Canyon, Ordesa y Monte Perdido National Park, Huesca, Spain (© Marisa Estivill/Shutterstock)

Aït Benhaddou, Morocco (© Grant Faint/Getty Images)

Balsamroot and lupines, Methow Valley, North Cascades, Washington (© Alan Majchrowicz/Getty Images)

Field of flags set up for Memorial Day (© Andrew Seegmiller/Getty Images)

Roussanou Monastery, Meteora, Thessaly, Greece (© Marius Roman/Getty Images)

Eurasian otters, Loch Spelve, Isle of Mull, Scotland (© Neil Henderson/Alamy)

A stand of slash pines and sawgrass prairie, Everglades National Park, Florida (© Jonathan Gewirtz/Tandem Stills + Motion)

Gunnerside, Swaledale, Yorkshire Dales National Park, England (© Derek Croucher/Alamy)