An hour and a half’s drive northwest of Dublin is a lake—or “lough” as they say in Ireland. By Irish standards it isn’t particularly big—at five miles long and only half as wide, there are 12 other loughs on the island that are bigger. No mountains tower overhead. No eagles soar. Yet its curiously green waters touch no fewer than four counties—Cavan, Longford, Meath and Westmeath. For flyfishers all over Ireland, and in Europe, the place is as legendary and full of mystery as its Irish Gaelic name: Loch Síodh Linn, “lake of the fairy pool.”

It’s better known as Lough Sheelin. For a few weeks each spring, Sheelin produces one of the most spectacular mayfly hatches you’ll see anywhere. During that time, some of the biggest brown trout in the Northern Hemisphere come to the surface to gorge on nature’s bounty. During certain evenings, when the conditions are right, you can see their dorsal fins protruding from the water as they cruise along, rising 10, 20, 30 times in quick succession, sucking down a bellyful of flies. Fly fishers come from far and wide to try to catch them. During the day they typically use subsurface flies, but the great prize is to take one of these big evening cruisers on a dry fly.

Dry fly fishing on Sheelin requires a gigantic leap of faith. You cast out and then track your fly as it bobs among countless naturals that are already on the water. Why, you ask yourself, as I found myself doing in May 2024, would a trout single out my fly from all the others? Yet somehow, if you’re lucky, and perhaps precisely because your fly looks a little different from all those naturals, from time to time the trout do.

People often speak of the luck of the Irish; on Sheelin, the Irish speak of little else. “Whatever kind of fisherman you are, you need to be lucky,” veteran boatman and guide Ned Clinton told me on my first day as he readied his boat for his clients. “I’d rather be born lucky than good. Please God, and today we’ll be lucky.” The fishing is hard enough to warrant such invocations. Plenty of people have fished Sheelin for days without ever hooking anything. In part, this is what makes the place so special, so seductive. It’s this that keeps people coming back.

Subscribe for access to this article plus the entire archive of The Flyfish Journal content—and receive a discount on products.