It is over two metres high, roughly fifteen metres across at its longest, and made almost entirely of fire-cracked rock and charcoal-darkened soil. A drain has been cut along its southern edge, and the eastern side shows signs of quarrying, as if someone once decided the material was useful for something more immediate than prehistory. A possible opening faces north, with an old stream bed curving in from the north-west, which tells you something about how the site once functioned.

This is a fulacht fia, a type of prehistoric cooking or industrial site found across Ireland in enormous numbers. The typical arrangement involves a trough dug into the ground near a water source, a hearth for heating stones, and the stones themselves, which were dropped into the water-filled trough to bring it to a boil. Over time, the cracked and spent stones were discarded in a horseshoe-shaped mound around the trough, which is exactly what survives here. The proximity to that old stream bed is characteristic; water access was the whole point. What makes the Tullylease example a little more interesting is that it does not stand alone. A second fulacht fia lies just 33 metres to the north, which suggests repeated or sustained activity in this particular patch of ground, though whether the two sites were used at the same time or centuries apart is not something the landscape can tell you.