I bet scads of anglers have walked on a bridge or on a high trail in the mountains, looked at the water far below, and wondered, Has anyone ever fished that? I often follow that with: There have to be some big lunkers down there, and It would be so cool to find out. One summer day, I was standing on the edge of a cliff looking down at such a place: the North Platte River in Wyoming’s Fremont Canyon.

I knew the fishing upstream to be excellent, but I wanted to find out if it was even better down where no one could reach it. My friend, Doug Heggart, and I had had a blast fishing that morning. We’d double-hooked large trout with our tenkara rods and enjoyed an unusually windless day. Then, knowing of my other main passion, rock-climbing, Doug took me up the canyon. I peered down the sheer walls, my gaze going back and forth between potential climbing lines and the pools in the water below. There have to be some big lunkers down there, right?

A year later, I recruited another friend, Steve Conrad, to return to Fremont Canyon and help me answer that question. Like me, Steve is a fly-fishing climber. Normally, my fly gear is as simple as it gets: a telescopic tenkara rod, line and fly. I leave the reel and other stuff behind in favor of this Japanese method of fly-fishing that I discovered and introduced to the US in 2009. But in order to fish Fremont Canyon, we also needed climbing ropes, and a decent amount of hardware, harnesses, climbing shoes… perhaps because my other activities are so gear-intensive, I keep my fly-fishing simple.

“Well,” said Steve, “I guess we’ll find out if the rope is long enough.”

Attached to the rope via a harness and rappel device, I stepped over the edge and started my descent. The granite walls were perfectly vertical. I split my attention between the rap, the water below and the features on the rock I’d have to climb later. We had eyeballed a possible climbing route earlier, but didn’t know for sure if we could get out—so far, it looked do-able.

The spot where I landed turned out to not only provide one of the few places in the area with rocks in the stream to stand on, but it also held some of the only fishy-looking features in this stretch of river: A half-dozen tiny islands created current breaks that funneled food and provided calm pools perfect for trout to hang out in. The water was murky, but readable and deep. Tenkara is often translated from the Japanese as “from the heavens.” Descending into the river like this, the name struck me as particularly appropriate today.

Steve hooked into the first fish and called for help with netting it—showing us, immediately, that fishing here was going to be a team sport. As the day went on, we boulder hopped, stretched and lay on rocks to net each other’s fish. Salvation came from the fact that by using a rod without a reel or running line, we were forced to hold tight and battle the fish in relatively small areas. If we’d allowed these trout to run downstream and around boulders, we surely would have lost.

After landing a few fish and realizing the splashes and commotion had likely ruined the element of surprise, our thoughts turned to finding the line of least resistance back up the cliff. We eyeballed the rock face and picked a crack. Cracks often offer the “easiest” route, but they can come with a surprise.

We collapsed our rods, untied the line from the rod tip, put the kits in my pack, tied the ropes to our harnesses and started up. Our line looked challenging but fun—until I heard Steve groan. The crack had turned into an off-width, so called because it opens up into the wrong width for classic crack techniques. In general, Steve and I avoid off-widths because of the exhausting Houdini-like contortions required to climb them, but here we had no choice.

We eventually huffed our way to the top of the cliff, and looked back at our day far below the canyon rim. I finally got to answer the question I had so often asked myself when walking high up above a body of water. Yes, of course, there were fish.

Daniel Galhardo is the author of Tenkara: A complete guide to the techniques, gear, history, and philosophy of tenkara, the Japanese method of fly-fishing. A manifesto on fly-fishing simplicity. You can order it at tenkarausa.com.