Birr Castle Demesne

Birr, County Offaly, Ireland, Ireland

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Birr Castle Demesne is a historic estate in Birr, County Offaly, centred on Birr Castle, the ancestral home of the Parsons family, Earls of Rosse. The site has been occupied since the 12th century and combines centuries of history with extensive gardens, parklands, and woodland walks. The estate is internationally famous for its contributions to science and astronomy. In 1845, William Parsons, the 3rd Earl of Rosse, built the “Leviathan of Parsonstown,” which was the largest telescope in the world for more than 70 years and played a major role in advancing the study of galaxies and the universe. Today, Birr Castle Demesne is one of Ireland’s leading heritage attractions, featuring beautiful gardens, rare trees and plants, a science centre, and historic scientific instruments. Its unique blend of history, nature, and innovation makes it one of County Offaly’s most remarkable landmarks.