Through the Sister Parks program, national parks in the United States share a mission of environmental stewardship with similar parks around the world.

Participant countries enter a five-year agreement, overseen by the U.S. Department of State’s Office of International Affairs, with the United States allowing park rangers from both nations to share conservation tips and best practices for caring for important parks, sites and monuments.

Over three dozen Sister Park partnerships link parks in the United States with ones in 32 other countries.

Here are five of these Sister Park partnerships, united by a common goal of protecting the Earth and important cultural sites.


 

Castle on lake with swan; mountain goat on cliff with mountains in background (© Gareth McCormack, © Viktor Posnov/Alamy)
Left: Ross Castle, Killarney National Park, Ireland. Right: Rocky Mountain Goat, Bearhat Mountain in Glacier National Park, Montana (© Gareth McCormack, © Viktor Posnov/Alamy)

On March 21, the governments of the United States and Ireland signed a joint agreement establishing Glacier National Park in Montana and Killarney National Park in County Kerry as Sister Parks. Irish legend says the builder of Ross Castle, O’Donoghue Mór, lies beneath the lake and wakes up every seven years to ride a white horse around it. While no such legends exist for Glacier National Park, it does encompass over 404,000 hectares and 130 glacial lakes.


 

U.S. flag waving over water with low white building in distance; curved white building behind wall of names with several people in foreground (© Carolyn Kaster/AP Images, © Emma Frater/Alamy)
Left: World War II Valor in the Pacific, Pearl Harbor, Hawaii. Right: Welcome Wall at the Australian National Maritime Museum at Darling Harbour, Sydney (© Carolyn Kaster/AP Images, © Emma Frater/Alamy)

The USS Arizona Memorial, part of the World War II Valor in the Pacific National Monument, in Oahu, Hawaii, and Australia’s National Maritime Museum in Sydney both honor their countries’ naval endeavors. The U.S. government also sponsors a gallery inside the Australian museum.


 

Alligators in swampy water; jaguar in jungle (© Dennis MacDonald, © Andrey Gudkov/Alamy)
Left: Alligators, Everglades National Park, Florida. Right: Jaguar, Pantanal National Park, Brazil (© Dennis MacDonald, © Andrey Gudkov/Alamy)

The Everglades National Park in Florida and Pantanal National Park in Brazil are both wetland conservation areas. The latter lies within Brazil’s Pantanal region, one of the world’s largest freshwater wetland ecosystems, while Everglades National Park protects 20% of Florida’s original tropical wetlands and is the largest tropical landscape in the United States.


 

Wooden walkway inside cavern; man in small fishing boat at night with mountains in background (© Daniel Borzynski, © Bill Coster/Alamy)
Left: Mammoth Cave National Park, Kentucky. Right: Cormorant fisherman, South China Karst World Heritage Site, China (© Daniel Borzynski, © Bill Coster/Alamy)

Mammoth Cave National Park in Kentucky partners with the South China Karst World Heritage Site in Guangxi province. The South China Karst World Heritage site sprawls over 97,125 hectares and contains significant karst landforms — underground drainage systems formed by the gradual dissolution of rocks. Mammoth Cave, similarly, is the longest cave system known and is home to a rich diversity of plant and animal life.


 

Trees and shrubs overlooking lake and mountains; breakfast table and chairs outside small dwelling overlooking forest and lake (© Spring Images, © Andreas von Einsiedel/Alamy)
Left: Lake Roosevelt, Washington state. Right: Hacienda overlooking Spioenkop, KwaZulu Natal, South Africa (© Spring Images, © Andreas von Einsiedel/Alamy)

Lake Roosevelt National Recreation Area in Washington state is “sister” to Spioenkop Nature Reserve, a protected area in KwaZulu-Natal, South Africa. The Spioenkop reserve is 4,400 hectares of diverse ecohabitats while Lake Roosevelt is connected to the Grand Coulee Dam, a historic hydroelectric plant.