Midway up the trail comes the pinch that gives Conkle's Hollow its reputation: rims roughly three hundred feet apart with sandstone walls rising more than two hundred feet between them, and a gorge floor cool enough to function as a living Ice Age archive. Conservation crews keep close watch here — the preserve's old eastern hemlocks are monitored and treated against an invasive pest, and so far the protectors are winning — one reason the stay-on-trail rule is absolute. A rugged rim trail traces the unfenced cliff tops far above; it is no place for children, and the gorge-floor path remains both the family route and the better view of the walls.
Feel that? The air just turned cooler — noticeably cooler than the parking lot you left ten minutes ago. Pause here a moment and look at how the hollow has closed in around you. The walls stand better than two hundred feet now, and this is the pinch: barely three hundred feet across, rim to rim. Folks often call this one of the deepest gorges in Ohio, and standing on this spot, you won't feel like arguing.
Now look up that dark slope, and look closely at the trees. Eastern hemlock, with the short flat needles. Yellow birch. Canada yew low to the ground, and teaberry right down by your feet. Here's the secret: that is not really an Ohio forest. It's a Canadian one. When the Ice Age ended and the cold retreated north, the chill stayed trapped in deep slots like this — heavy cold air pools down here and never quite leaves — and the northern forest stayed right along with it. You're walking through a refrigerator the glaciers stocked and forgot, and these trees have been keeping fresh in it for some ten thousand years.
One more thing about those hemlocks. A tiny invasive insect has developed a taste for them — but the tree doctors caught it early here, and they're treating these giants and winning so far. The forest around you is being watched over.
And yes, there is a rim trail up along that edge. It's steep, unfenced, and meant for experienced hikers without kids in tow. Down here on the floor is the masterpiece anyway. Keep going — the hollow has one more room to show you.