MADISON, Wis. — Earlier this month, Madison, Wis., was host to the city's 14th annual Frozen Assets Festival. "When our lakes are frozen, they are truly our greatest asset," says James Tye, executive director and founder of Clean Lakes Alliance, the nonprofit that hosts the festival.
This time of year, frozen lakes are a part of life here. The city was built on an isthmus — a thin strip of land between two bodies of water. Lake Mendota and Lake Monona border the city's historic downtown on either side, with the strip of land running about a mile wide at its thinnest. The lakes are visible from many places in town. In wintertime, ice fishing, skating, ice sailing and snowshoeing are all common sights.
Historically, people valued the ice for other reasons. "There's a long history of ice harvesting in this region," says Hilary Dugan, a limnologist — someone who studies inland waters — at the University of Wisconsin, Madison. "So [there was] just a lot of commercial activity on these lakes, cutting blocks of ice out of the lakes all winter."
Frozen lakes were so important to the city that records of when the ice froze each year go back more than 100 years. Today, there's even a contest where people guess the day Lake Mendota will freeze. On average, that date is getting later.
"We've actually lost about a month of lake ice duration here in Madison," says Dugan. And the ice that does form isn't always safe. "Traditionally, these were lakes that froze really safely every winter. And that's becoming less — we're less confident in that, going into the future."
As climate change accelerates, fluctuations in winter temperatures increase, which leads to unpredictable ice conditions. That was the case two years ago, in 2024, when the on-ice portion of the Frozen Assets Festival was cancelled. "At that point, it was just too warm. There were weird little things going on [on the ice], and so we called it to be on land," says Tye.
This year, Lake Mendota had over a foot of ice in early February, which was more than enough to hold the festival's 1,000-plus attendees. The event featured kite flyers, sky divers, ice hockey and the only 5K that takes place solely on ice.
Here is a selection of images from this year's festival:
Copyright 2026 NPR
