Brownshill Dolmen, also known as Browneshill Dolmen, is a massive megalithic portal tomb located in County Carlow, Ireland. Built between 4000 and 3000 BC, this ancient structure features a capstone that weighs around 150 metric tons, making it one of the heaviest in Europe. The tomb is flanked by two large upright stones supporting the capstone, with a gate stone blocking the entrance. Despite its age, the dolmen has not been excavated, adding to its mysterious allure. Visitors can easily spot this impressive monument from the nearby road, making it a must-see for history buffs and curious travelers alike.