Like robins and maple sap, Lake Superior ore boats aren't much affected by the never-ending winter that humans find so annoying.
Toward the end of March, ice-breakers arrive to clear the shipping lanes, allowing the first boats to leave winter layup, kicking off the spring shipping season.
Then traffic starts to move within Lake Superior, and when the Soo Looks open on March 25, boats arrive from other Great Lakes.
Most people don't think of Duluth as a beach town.
It's a little chilly, for one thing. But the port city has six miles of sandy beach along the largest freshwater sandbar in the world.
Just over the Aerial Lift Bridge, Park Point is where Duluthians play. They hike and run on a two-mile trail through forest and dunes. They paddle canoes and kayaks. They hang out on the beach, watching waves in winter and braving them in summer.
When it's not cold or snowy enough in Duluth, the natives start to grumble.
This Minnesota port on Lake Superior loves winter, though it's not for weaklings.
The breezes that earned it the nickname "Air-Conditioned City'' will chill your bones in winter, and if you don't keep moving, you'll wind up as stiff as the bronze sculptures along the lake.
Thirty years ago, motorists whizzed right through Duluth on their way to Minnesota's North Shore, putting it into their rear-view mirror as fast as they could.
That changed in the early 1990s, when the rejuvenation of Duluth's lakefront started to transform this working-class port town into the belle of Lake Superior.
Now, it's packed from summer through fall, and rooms at its hotels and B&Bs can be hard to come by. It's a Cinderella story, really.
Once, a wind-whipped sand spit was not the most desirable address in Duluth.
Today, tourists want to hang out on Canal Park and stay in beach cottages on Park Point, just beyond the Aerial Lift Bridge. But the Ojibwe preferred the calmer estuary of the St. Louis River, which flows into Lake Superior at what today is Duluth-Superior Harbor.
The French explorer Daniel Greysolon, Sieur du Lhut, for whom the city was named, didnt waste much time on the lakefront when he arrived in 1679.
Duck confit with honey aioli and caramelized shallots. Grass-fed beef medallions with bacon potato croquettes. Vanilla cake with white-chocolate espresso frosting and pumpkin ale truffles.
Yes, you can get that in Duluth.
The restaurants in this Lake Superior port town haven't always had a great reputation. But that's changed.
On Duluth's Hawk Ridge, a bird in the hand is worth at least two in the sky.
They're impressive when spotted overhead. But up close, it's easier to get to know a bird say, the northern goshawk, a fierce predator whose image once adorned the helmet of Attila the Hun.
As she held a young goshawk by the legs, naturalist Willow Maser struggled to make herself heard above its high-pitched screeches.
One March, I went up to Duluth but woke up in Siberia.
Twenty inches of snow had fallen overnight. A savage 70 mph wind was howling around the glass-walled lobby of the Willard Munger Inn. Swirling snow had turned the air white.
But then my niece and I noticed cars crawling along Grand Avenue. Then more cars. So we bundled up, got in our car and, to our surprise, made it all the way across town to Lester Park.
In Duluth, you can lead a child to water but just try leading her away.
Mom, itd be worth moving to Duluth just so we could go to this beach a lot, said my daughter Madeleine, jumping from rock to rock at Brighton Beach.
Duluth is one of the best places in Minnesota to take children. On Canal Park, the lineup of tourist attractions can keep a family entertained for days.
To many people, it's still a revelation that Duluth is one of the best places to hike, not just in Minnesota but in the nation.
It's a city of 86,000, after all. But this hillside town, once called the San Francisco of the North, has spectacular terrain for trails, along glacial beach terraces high above Lake Superior and on creeks that tumble down rocky ravines.
Many hikers blow through Duluth on their way to sections of the Superior Hiking Trail farther up the North Shore. But the 43 miles that cross Duluth provide the most concentrated scenery on the entire trail, lake views and waterfalls included.
In Duluth, there's water a lot of water beyond the big lake and the Aerial Lift Bridge.
The St. Louis River is the largest U.S. tributary to Lake Superior, and it creates a huge estuary as it approaches the lake.
Fishermen and bird-watchers have frequented it for years, and more are showing up as the water becomes cleaner. Sturgeon have come back, eagles nest, and 70 percent of the birds seen in Minnesota come through on fall and spring migrations.
A few steps into the forest, and it hit.
The tang of cedar bark and pine needles, moistened by droplets of mist from waterfalls. The loamy richness of earth carpeted by ferns.
It was that north-woods perfume all Minnesotans instantly recognize, a powerful eau de outdoors that gladdened my heart and also made it sink with the realization that I'd stayed in the city far, far too long.
When the ore boats start arriving in Duluth, the tourists soon follow.
Fifty years ago, ships were part of the industrial landscape on Canal Park, and no one thought they were all that romantic.
But things have changed. Today, these hulking big boats are to Duluth what killer whales are to Sea World. Because, boy, do they make people come running.
In 1890, Duluth was a treasure chest waiting to be opened.
It sat at the foot of Lake Superior, connected to the steel mills and cities of the East by water. White-pine forests lay to the south and west, and rich veins of iron ore to the north.
It couldnt fail to make money for the men who came to tap its riches, and it didnt.
In summer and fall, festive Canal Park draws the crowds. But when cold winds blow in winter, a brewery suddenly looks much better.
Started in 1882 as Fink's Lake Superior Brewery, Fitger's was a mainstay in Duluth, surviving Prohibition but not industry consolidation. It closed in 1972 and almost was razed, but the sprawling building on the lake reopened in 1984 as a hotel, restaurant and shopping complex.
Now, the complex also boasts a day spa, a nightclub, a brewery, a coffeehouse and shops everything anyone could want for a little getaway, all under one roof.
In Duluth, there's water, water everywhere and nary a place to swim.
In Lake Superior, anyway. If you try to cool off in the frigid lake, you'll probably run out immediately, shrieking.
Early tourist brochures touted Duluth as "The Air-Conditioned City,'' and the vast waters of the big lake keep it cool, at least until July. Then it heats up, and the locals few of whom have actual air conditioners head for water.
It took a servant a day and a half to polish one of their chandeliers. It took three Norwegian craftsmen three years to carve their woodwork.
Still, it's hard to begrudge Chester and Clara Congdon their nice things, because apparently they were very nice people.
Chester gave 11 miles of Lake Superior shoreline to the people of Duluth and made sure it was preserved for them in perpetuity. Clara donated her time and resources to the Methodist church; her servants ate the same meals she did and were paid twice as much as others.
Twenty years ago, most beer drinkers thought porters work on the railroad, blondes have more fun and a craft requires popsicle sticks and yarn.
My, how things have changed.
In the United States, craft beer still claims only 11 percent of sales. But each year, more and more drinkers cross over from the lite side, and hundreds of new craft breweries spring up to serve them.
It's a hot Saturday in Duluth, and it seems as if every tourist in town is on Canal Park.
But a few have found their way to a quieter spot, on Amity Creek above downtown.
Just off Skyline Parkway, some 10-year-olds are having a great time climbing rocks and splashing in a pool beside a waterfall, thanks to a mother who went to college in Duluth. She's brought her daughter's soccer team to play and cool off between tournament games.
Remember all those summers when you looked longingly at Lake Superior, wishing you could swim in it for more than a minute without going numb? The summer of 2012 wasn't one of them.
Non-stop, beastly hot temperatures mellowed the waters of the big lake, turning it into the world's largest swimming pool.
Water-surface temperatures pushed 75 degrees on the notoriously cold stretch between Duluth and Grand Marais. That's was the warmest in a century and 20 degrees higher than normal for mid-summer.