Ten years ago, a woman living near Dallas, gripped by wanderlust and the sadness of impending empty-nest syndrome, went to a search engine and typed in "waterfalls" and "hiking." That's how I came to be sitting on a rock outcropping beside a river as it churns foam while rushing down a narrow gorge - not in Colorado or West Virginia but Minnesota. Yes, Minnesota.

That was where Yahoo! directed her, a 1,500-mile distance from the Alamo. And now, five years after I married her and persuaded her to move to Chicago, that's where I've come to overcome my skepticism that the Great Lakes region has anything to rival the rugged trails and breathtaking vistas of Colorado (where we spent a recent vacation) or the Adirondack mountains of New York, which we've visited twice. It didn't take long to dispel every doubt.

We're only a mile or two from Lake Superior, which contains more water than all the other Great Lakes combined, and all that water has to come from somewhere. More than 300 rivers and streams empty into the lake, including many in the stretch of Minnesota between Duluth and Grand Portage, on the North Shore.

The Cascade River, which we are hiking today, drops 900 feet in its last three miles, and even at the low water levels prevailing on our visit, it was obvious how the river got its name. Every 10 steps, there is another view of a zigzag corridor of waterfalls. For ambitious hikers, there is a steep 7.8-mile loop. A 2.6-mile round trip will take you to the top of 600-foot Lookout Mountain, which furnishes views of Superior. Casual sightseers, however, need walk only about 100 yards to mount a platform with a close-up view of a 50-foot fall.

We got started late on the Cascade trail and made slow progress, partly because of the demanding uphills but more because of frequent stops to marvel at the views - and, in the case of my professional freelance photographer wife Cyn, to frame postcard shots. So two hours up the trail, we decided to retrace our steps. The views were almost as good going back.

The rivers and falls are mesmerizing, but it feels a waste not to make some use of that inland sea. So one bright morning, we showed up at North Shore Expeditions in Grand Marais for a kayak outing with instructor Bryan Hansel, a cheerful Iowan. He says the water has been rougher lately, but today it's as smooth as buttermilk. We paddle out of the harbor and turn south, with hardly another boat in sight. We eventually beach near a waterfall, of the Fall River, visible only from Lake Superior. After half an hour of rock hunting - another of Cyn's obsessions - she loads her finds in the cockpit of her kayak, which is consequently a bit nose-heavy on the trip back.

We spend the rest of the day exploring Grand Marais, reading at our rented cottage and assembling our gear for the next stage of our trip. Early the next morning, we drive to Grand Portage to board the Voyageur II, a passenger ferry that makes the two-hour passage to Isle Royale, the biggest island in Lake Superior and the least visited national park. It's also part of Michigan, though just off the Minnesota shore.

It's a sunny day, and the water is again calm. We chat with Sarah, an intrepid 50-something from Massachusetts who plans to spend nine days camping solo in the backcountry.

On arrival at Windigo, on the far western side of the 46-mile-long island, we get a jolly orientation from ranger Cindy Crosby of Glen Ellyn, who delivers a warning. "I came here as a backpacker and I got one of these," she says with a smile, brandishing her badge. "You think you're just here for a short visit, but you could end up wearing gray and green for the rest of your life."