The Rosse Observatory, located in County Offaly, Ireland, is renowned for housing the Leviathan of Parsonstown, a massive telescope built in the 1840s. This telescope was the largest in the world for over 70 years and played a significant role in advancing the field of astronomy. The observatory was established by the 3rd Earl of Rosse, who was an influential astronomer. Today, the site is a popular tourist attraction, showcasing the historical significance of the telescope and its contributions to our understanding of the universe.