There’s a Mysterious ‘Vanishing Lake’ in Northern Ireland That Fills up and Empties Every Few Hours
Published Sept. 4 2025, 11:45 a.m. ET

A man standing by a lake surrounded by clusters of bushes and plants.
With rugged cliffs and chalky landscapes, there’s a moorland region in Northern Ireland that hides a mysterious magic. Tucked within County Antrim, along the Ballycastle road, is a lake that displays an uncanny behavior - it appears and disappears in fleeting glimpses. The mystery, however, is much simpler, from the perspective of science, as described by The Geological Society of London. Nicknamed “The Vanishing Lake,” Loughareema sits in a remote location, engulfed by a blanket bog, a treeless, peatland habitat with waterlogged grounds.

Loughareema vanishing lake near Cushendun, County Antrim, Northern Ireland, United Kingdom, Europe.
The geology of the lake is so puzzling that it has caused scientists to scratch their heads over the past many years. Loughareema can be empty in the morning and suddenly be filled by lunchtime, only to be emptied again by dinner. This mysterious phenomenon has prompted curious scientists across the globe to flock to this region of Northern Ireland and investigate it. When Paul Wilson, a hydrogeologist at the British Geological Survey in Belfast, Northern Ireland, visited the lake, he wasn’t surprised. There was nothing on the surface that hinted that the lake was mysterious. But another visit at a different time revealed something baffling.
An elaborate examination of its geology made the entire picture clear. The flickering behavior of the lake stems from its underground drainage system that carries the water to a large spring in the Carey River, about 1.6 miles away. Three streams flow, intersect, and spill into the lake. But the exit point of these waters is only one drain, concealed at the lakebed. This drain, according to Wilson, dramatically gets blocked and unblocked, all by itself, which results in the fleeting appearance of the lake’s waters, followed by stark disappearing episodes during the drier seasons.

A lake surrounded by bushy boughs
Wilson and his fellow scientists were unable to decipher how exactly this underground system works, but it surely bestows a fascinating geological mechanism to the lake, using which it can drain empty just within a few days, only to be filled up again. "Loughareema is a dynamic landscape, and on approach to the lake, it's exciting to guess what state it will be in," described Wilson. "The water disappears into an underground drainage system, the details of which we currently know very little about."

Loughareema vanishing lake near Cushendun, County Antrim, Northern Ireland, United Kingdom, Europe
As Wilson explained to the Geological Society, when the water from the streams flows into the lake, it brings along with it the debris and dust it picked up on the way. All this dusty sediment starts sinking and accumulating on the lakebed, eventually covering the drain. Once the drain hole is completely choked by the sediment, the water level starts rising faster. And when the water level rises to a certain level, the pressure it exerts downwards automatically unblocks the drain. This is when the water starts draining down again, and the lake disappears.

Pristine lake surrounded by trees and bushes glittering in daylight
It’s not just this unusual drainage system that makes Loughareema so mysterious. There’s a road that runs through the middle of the lake. Legend has it that some people in horse carriages were riding on the road above the lake during the night. When their carriages stomped onto the road, the lake was dry, but by the time they reached the middle, the waters reappeared and swallowed up the humans, their horses, and the carriages. This was back in the 19th century. But even today, when the skies become blanketed by nights, locals are frightened to sneak into the territory.