Historical records show that a fortification existed here as early as 1574, when it belonged to Walter Burke, a member of one of Galway's most prominent Norman families. The castle appears to have survived through the centuries, still standing in the late 18th century according to archival files, though its days were numbered.

In the early 19th century, the decision was made to demolish the old castle entirely. Rather than simply abandoning the site, the stone from the structure was repurposed to construct the small quay that visitors can see today. This practical recycling of building materials was common practice in Ireland, where good stone was valuable and castles that had outlived their defensive purpose often became convenient quarries for local construction projects.

Today, no visible traces of the original castle remain above ground at Pollacushlann. The quay built from its stones serves as the only physical reminder of the fortification that once guarded this stretch of Oranmore Bay. The transformation from medieval stronghold to working quay reflects the changing needs of the local community; where once defence was paramount, maritime access and trade became the priority as Ireland moved into the modern era.