Sheshoon and its extension Brownstown are approximately six miles due west of Gilltown. Sheshoon is the oldest continuously operative stud in either Ireland or England and was the first Irish Farm purchased by the Aga Khan. Although the original property amounted to approximately 200 acres, it has grown to approximately 1200 acres through development over recent decades, and the incorporation of Brownstown stud.

In spite of its longevity, Sheshoon has undergone thorough redevelopment in recent years. Improvements to old traditional buildings have been made and new, state of the art barns have been built to ensure the best possible care for all the stock .

The majority of the Aga Khan mares and their stock are based in Sheshoon, where many of the yearlings are reared. The foaling unit is also located in Sheshoon and serves both Aga Khan and visiting mares .