Alton Bay, the Only FAA-Approved Ice Runway in the Lower Forty-Eight, Where You Land Your Airplane on a Frozen Lake in New Hampshire

SUMMARY: Alton Bay (B18) on New Hampshire’s Lake Winnipesaukee is the only FAA-recognized ice runway in the lower 48 states.

Alton Bay, New Hampshire is home to the only FAA-recognized ice runway in the lower 48 states. Each winter, when the ice on Lake Winnipesaukee grows thick enough, a crew of local volunteers plows a runway directly onto the frozen surface and opens it to pilots under the identifier B18. It is the same site that serves as a seaplane base in summer - and for a few weeks a year, it becomes one of the most extraordinary airports in America.

What Is the Alton Bay Ice Runway?

Alton Bay sits at the southern tip of Lake Winnipesaukee, the largest lake in New Hampshire, in the state’s Lakes Region. In summer, it operates as a seaplane base, where floatplanes taxi up to the town dock so pilots can walk into town for lunch.

In winter, the bay freezes and the same location transforms. Volunteers plow roughly 2,600 feet of runway onto the ice, marking the edges with pine boughs and cones stuck directly into the surface. The airport carries the identifier B18 and appears on aeronautical charts - the only ice runway in the contiguous United States to hold an official FAA identifier.

The ice itself can reach remarkable thickness. During a good season, the plowed strip sits on roughly 30 inches of solid black ice, with more than 100 feet of cold water beneath it.

How Thick Does the Ice Have to Be?

The magic number is 12 inches. The runway will not open until there are at least 12 inches of good, solid, clear ice - and the volunteer crew, led for many years by Paul LaRochelle, will not compromise on it.

They drill test holes, measure the ice, and monitor conditions constantly. If the ice isn’t ready, nobody flies. This caution is exactly why pilots trust the field enough to bring their families out onto a frozen lake in the first place.

What Is It Like to Land There?

On a clear February Saturday, the ice runway draws crowds - often 100 to 200 airplanes in a single day, flying in from across New England, New York, and as far away as the Carolinas.

On approach, the visual picture is unlike anything in normal flying: a white ribbon plowed onto a white lake, lined with small evergreens, snow-covered hills off the wingtips. Every instinct tells a pilot that a runway does not belong there. Then the wheels touch down on ice smoother than most pilots expect.

How Do You Fly an Ice Runway Safely?

Landing on ice demands stick-and-rudder precision. A few key points local pilots emphasize:

Expect strong performance. The cold, dense winter air gives engines and wings excellent lift. Aircraft climb off the ice noticeably faster than they would in summer heat.
Treat braking as a suggestion. There is essentially zero grip. Plan a long, smooth rollout and keep the aircraft straight with rudder rather than standing on the brakes.
Taxi slowly and gently. Be light on the throttle. A swinging tail on frictionless ice can quickly get away from you.
Respect the crosswind. This is the biggest hazard. Without tire grip, a crosswind can slide an aircraft sideways down the runway like a hockey puck. Pilots watch the wind closely because their control depends on it.

The volunteers post current conditions, including ice thickness and braking reports, so pilots can make informed decisions before they arrive.

The Scene on the Ice

The ice runway is really a winter festival. Airplanes park in neat rows alongside ice-fishing shacks, cars driven out onto the lake, kids playing in the snow, and the smell of woodsmoke, cold air, and a little avgas.

The culture is warmly social - pilots open their cockpits to curious kids and grandparents alike. Families fly in together; even veteran pilots with 40 years and thousands of hours describe getting butterflies every single time they land on the frozen lake.

And because tradition demands it, most visitors follow the “hundred-dollar hamburger” rule: park on the ice, walk up into the town of Alton Bay, and get a hot breakfast at one of the local spots near the water before flying home.

Why the Ice Runway Matters

Winter grounds many pilots. Alton Bay does the opposite - it gives New England aviators a reason to fly during the coldest, darkest part of the year and builds a community around it.

It is also fragile. In some winters the ice never gets thick enough, warm spells make it unsafe, and the crew keeps the runway closed for an entire season. That uncertainty is part of what makes each successful season feel like a gift.

If you plan to fly in, don’t show up unprepared. Talk to someone experienced, get a checkout on the technique, watch the winds, and respect the posted braking and crosswind conditions. Done right, it is one of the most rewarding experiences in American aviation.

Key Takeaways

Alton Bay (B18) on Lake Winnipesaukee, New Hampshire is the only FAA-recognized ice runway in the lower 48 states.
It operates as a seaplane base in summer and an ice runway in winter, with a plowed strip of about 2,600 feet.
The runway opens only when the ice reaches at least 12 inches thick; volunteers led by Paul LaRochelle measure it carefully and close the field when it isn’t safe.
Ice flying demands minimal braking, gentle taxiing, and sharp crosswind awareness, while cold dense air rewards pilots with excellent climb performance.
On a busy clear day, 100 to 200 aircraft fly in from across the region, turning the frozen lake into a winter aviation festival.