This is a cooking pit (fulacht fiadh) at Drombeg Stone Circle outside of Glandore west of Rosscarbery, County Cork, Ireland. Stones were heated in a fire-pit and then placed in the trough to heat water used for cooking. Enough hot stones were added to bring the water to a boil. As the stones cooled they were taken out and replaced with more hot stones until cooking was complete. Drombeg Stone Circle is also known as the Druid’s Altar. There are various dates given for the age of the circle. It is believed to date from the Bronze age, and was in use 1,000 years BC; some say it’s way older. No matter it’s exact age, there is no disputing it’s old. If ancient sites speak to you, it’s worth a visit. Happy St. Patrick’s Day!