HILO >> Biking to the top of the 13,796-foot Mauna Kea volcano might seem like a daunting undertaking for many people, but it’s just another adventure for a globetrotting Swiss couple with their four children.

Dario and Sabine Schwoerer so far have navigated more than 60,000 nautical miles and climbed the highest peaks on five continents. After Mauna Kea, they will sail for Alaska, where they will climb Mount McKinley, North America’s highest mountain at 20,320 feet, the Hawaii Tribune-Herald reported Thursday.

So far, they’ve conquered Mont Blanc in Europe, Aconcagua in South America, Mount Kosciuszko in Australia, Mount Everest in Asia and Kilimanjaro in Africa.

Dario Schwoerer, 44, and his wife, Sabine, began their odyssey in Switzerland in 2000. The family travels aboard a solar-powered, 50-foot sloop. They plan to spend the winter in Alaska and then sail the Northwest Passage to the Atlantic Ocean.

That will be only the first half of their quest to “figure-eight” the continents of North and South America. They’ll take the Panama Canal back to the Pacific, then south around Cape Horn to the Atlantic again, back through the canal and up the western coast of the North American continent.

They diverted from their figure-eight course around the Americas to make the Hawaii island stop specifically to tackle Mauna Kea.

The bike ride to the summit of Mauna Kea is planned for today.

The family sailed into Hilo’s Radio Bay from Panama on Tuesday after 50 straight days at sea with 7-year-old Salina, 6-year-old Andri, 3-year-old Noe and 1-year-old Alegra, as well as two volunteers.

Two of the children were born in Patagonia, one in Australia and the fourth in Singapore.

When Salina was born in Patagonia, Dario said he cut the umbilical cord with a Swiss Army knife.

When that story reached the Swiss ambassador, he told his friend, who owns Victorinox, maker of the iconic multipurpose tool, and the family got their first major sponsor. The vessel’s sails sport a giant image of a Swiss Army knife.

Hilo is the first U.S. port they’ve visited in their journeys.

There have been some tense situations along the way. In 2005, they attempted to climb the highest peak in Antarctica, but couldn’t get there due to the volume of packed ice in the sea. After turning back, their vessel hit a floating container and was seriously damaged.

Their vessel made it to Patagonia, but there were no boat repair facilities that could get them back under sail. They were stuck for 18 months before they could get the materials and equipment needed to make their craft seaworthy again.

The couple expects their journey will end in 2017 after 18 years of ocean adventures.