They came to the North Shore from all over the state, venturing onto frozen Lake Superior with fishing lines that dropped as deep as 250 feet.

Using lures as heavy as hockey pucks to withstand underwater currents, they left with wild-caught lake trout and memories of an extraordinary Minnesota angling experience.

“Almost every time we went out there we caught a laker or two,’’ said Carson Spohn, 30, of Duluth. “There’s only so much staring down an ice hole that you can do, but this was definitely a good year up here.’’

Minnesota Fisheries Chief Brad Parsons called the long, largely uninterrupted ice season from Duluth to Two Harbors a “unique flash fishery.’’ It opened in early January and lingered into the fourth week of March, when Coast Guard cutters came along to break the ice and open shipping channels.

In a normal winter, anglers can count on brief setups of walkable ice around Duluth. But by February and March, it’s more common for people to be casting from shore into open water. In areas to the north of town that receive more wind, ice doesn’t get as thick and it breaks up more often. In Two Harbors, winters can come and go without the formation of fishable ice.

But this year the lake stayed frozen so long that the DNR conducted a so-called creel survey to check whether the unexpected winter harvest cut too deeply into the 2019 management plan for recreational fishing.

The data, gathered on location by a DNR creel clerk, hasn’t yet been summarized. But Lake Superior Area Fisheries Supervisor Cory Goldsworthy said there were weekend days when the lake was dotted with 300 shelters and many more anglers — an uncommon sight. In many cases, anglers were trusting the ice to be strong enough to support four-wheelers, side-by-side ATVs and snowmobiles.

Lake Superior’s ice remained accessible even as deep snow and slush messed up a lot of inland lakes late in the winter.

“It was a pretty rare event,’’ Goldsworthy said.

Andrew Larson, whose job it was to interview those who were fishing, said catch rates weren’t high. But those who invested reasonable lengths of time were usually rewarded with nice fish. In shallower waters, anglers were targeting coho salmon and herring. In some cases, steelhead would bite. The lake trout were out in deeper water, at the bottom.

“The deeper they went, the better they did,’’ Larson said. “But most people didn’t fish much deeper than 200 feet.’’

As the word spread on social media, he said, “we had people up here from all over the state.’’

The majority of fishing took place relatively close to shore by people on foot, Larson said. But others fished as far out as a mile. In the area around Two Harbors, Lake Superior drops off steeply fairly close to shore.

Spohn said this year’s ice-fishing season on Lake Superior was so lengthy that it nearly collided with this weekend’s traditional opener for open-water trout and salmon on Wisconsin’s Bois Brule River near Duluth.

“The ice just kind of pushed out this morning,’’ he said Friday.