Birr Castle

Birr Castle

A castle of science and gardens

In the very centre of Ireland, in County Offaly, stands Birr Castle — a place famous not for battles but for science, gardens and discovery. Home to the Parsons family, the Earls of Rosse, for centuries, Birr is surrounded by one of the most beautiful demesnes in Ireland and holds an astonishing treasure: a giant telescope that, in its day, was the largest in the entire world.

The home of the Parsons family

The Parsons family has lived at Birr since the early 1600s, and the castle they built and rebuilt over the centuries is a handsome Gothic-style mansion, still a family home today. But what makes Birr truly special is the curiosity and inventiveness of its owners, who were fascinated by science, engineering and the natural world.

The Leviathan of Parsonstown

In 1845, the third Earl of Rosse, William Parsons, completed an extraordinary machine in the castle grounds: an enormous telescope nicknamed the "Leviathan of Parsonstown". Its giant mirror, more than a metre and a half across, was the largest ever made at the time, and the whole telescope, slung between two huge stone walls, was a marvel of engineering.

With the Leviathan, the Earl was able to see further into space than anyone before him. Most famously, he was the first to observe the spiral shape of distant galaxies — swirling islands of stars far beyond our own. For about seventy years, the Leviathan remained the largest telescope in the world, drawing scientists from across the globe to this castle in the middle of Ireland.

The great telescope has been restored and can be seen in the castle grounds today, a wonder of Victorian science.

A family of inventors

The Parsons family's genius did not stop with the telescope. Another member of the family, Charles Parsons, invented the steam turbine, a machine that would power ships and generate electricity around the world. Birr Castle celebrates this remarkable family of scientists and inventors in its science centre, which tells the story of their discoveries.

Spectacular gardens

Birr is also famous for its gardens and demesne, which are among the finest in Ireland. They include towering trees gathered from around the world, beautiful walks along the rivers that meet in the grounds, a lake, and one of the tallest box hedges in the world. The gardens change beautifully through the seasons and are a delight to explore.

Visiting today

Visitors can wander the magnificent gardens and demesne, marvel at the restored Leviathan telescope, and explore the science centre that tells the story of the Parsons family's discoveries in astronomy and engineering. The castle itself remains a private family home, but its grounds and science are open to all. Unique among Ireland's castles, Birr is a place where history, nature and the wonders of science come together.