A Burnt Mound is a prehistoric mound of fire-cracked stones, ash and charcoal.

Fire cracked stones are ones that have been heated on a fire either for boiling water, cooking, brewing, bathing or other purposes such as ritual activities. Tiny cracks in the stones caused by repeated heating and cooling are distinctive and can be seen on close inspection.
Burnt Mounds were created from the late Neolithic to the Early Medieval period, though many cluster in date around the Bronze Age. They are usually round or oval but can be crescent shaped. They can be a few meters wide and under 50 cm high or up to 3 meters high and 35 meters in diameter.
Usually, the mound is accompanied by a pit, basin or trough lined with clay, stone or wood and capable of holding water. In many cases, the Burnt Mounds are located near streams. A possible interpretation is that the mound is made of waste stones that had been used to boil water in the basin.
Burnt mounds aren’t easy to identify, and are often only understood from ground survey, geophysics or excavation.