Over the Edge in Tioga
A few weeks ago, Facebook ambushed me with one of those tantalizing little video clips showing a diver scootering past a sheer underwater wall. The caption claimed it was filmed in the Tioga Mine Pit, Cohasset, Minnesota. I’d never heard of it. The name alone sounded like somewhere you’d dump an old washing machine, not stage a scene worthy of a BBC nature special. But the wall in the video looked extraordinary—dark, plunging, and far too good to ignore.
Tioga is about 75 miles away, just past the improbably pleasant town of Grand Rapids, Minnesota. For an Iron Range settlement, it’s unexpectedly tidy—well-kept buildings, clean sidewalks, a whiff of mild prosperity. Many of its neighbors on the Range have that faintly desperate air, as if they’ve been holding their breath since 1974, waiting for the mining boom to return. Grand Rapids, by contrast, looks like it might even have a yoga studio.
The Tioga Recreation Area itself is compact but thoughtfully set up: boat launch, sandy beach, changing rooms, and water so clear it practically comes with a disclaimer. On the west side, a cliff drops straight into the water, but most of the shoreline slopes more gently. The sand at the beach is fine enough to feel tropical, until you notice it disappears into deep blue just 20 or 30 feet out. A couple of houses hunker on the shore, complete with floating docks, jet skis, and—most notably—a colossal rope swing fashioned from two telephone poles. One suspects the local ER staff are intimately familiar with it.
My pre-dive research was, frankly, disappointing. There are a few online videos, most in a resolution that would make Bigfoot look sharp. Curtis Lahr is the notable exception, giving a tantalizing glimpse of the wall, plus some submerged oddities—including, improbably, a plastic human skeleton walking a plastic dog. What I couldn’t find was a clear map of entry points or where, exactly, this famous wall lurked.
Gear checks complete, I put my face in and—wow. The visibility was ridiculous. It was like swimming inside a grand underwater cathedral—endless blue stained glass overhead, except without the uncomfortable pews or the guilt of falling asleep during the sermon.
Here we are at the shores of Tioga Mine Pit—once a blast furnace of industry, now shockingly clear water and charming depth lures you under.
We descended to the left, following a steep slope dotted with light vegetation until the bottom abruptly vanished into the blue. The top of the wall sat at about 65 feet. Heather gave me the “Shall we?” gesture. She knows I sometimes get twitchy at depth, so this was both a courtesy and, I suspect, a challenge. I nodded, and over the edge we went.
The wall was nearly vertical, its face mottled and ridged like something sculpted by lava and erosion rather than mining equipment. The clarity let sunlight reach deep, painting the rock in shifting gold and green. I could see 50, maybe 70 feet down along its face. We descended until Heather stopped, tapping the spool of line running up to our dive flag—it was taut. We’d reached the end. Depth: 85 feet, which I was perfectly comfortable with.
I began setting up a photo of Heather swimming toward me, only to glance at my depth gauge and see 99 feet. That’s my certification limit. I hovered carefully, shooting quickly, and that’s when we both noticed our flag line no longer went up. It trialed off at an alarming low angle behind us. Turning, we spotted the flag resting on a tiny ledge—at 117 feet.
In Tioga’s gin-clear depths, Heather recovers our dive flag—now less a safety marker than a dive decoration.
Heather swam for it while I ascended slightly, my no-deco time having evaporated to two minutes. She retrieved the flag, wound the line onto the spool, and carried it for the rest of the dive—a slightly comic touch, since the flag was meant to alert boaters to our position. Later we discovered the culprit: she’d pulled it under far enough that the foam float compressed and lost buoyancy.
Following the wall into the blue, Heather becomes a speck in a landscape so vast it feels like we’ve stumbled off the edge of Minnesota.
With NDL spent, we began a leisurely ascent, following the shoreline in the shallows for another half-hour. Here, the terrain was less inspiring—a steep slope, sparse vegetation, and almost no fish—but the visibility alone kept it magical.
We surfaced grinning, high-fived, and agreed this was a dive worth repeating. Which, if the forecast cooperates, will probably happen Monday.
