Former Olympic water polo champion Peter Montgomery lists Innisfallen Castle

Innisfallen Castle, the landmark gothic-style mansion after which Castle Cove is named, is for sale amid hopes of setting a record for the lower north shore.

This is the vast 8300-square-metre estate with the heritage-listed castle that was built at the turn of the last century by federal parliamentarian Henry Willis and now owned by a company headed by lawyer and former Olympic water polo champion Peter Montgomery.

Three generations of the Willis family called it home before maintenance and restoration costs forced them to sell it in 1988 for $5.25 million, making Montgomery only the second owner in its 117-year history.

Montgomery has never lived in the residence, instead calling Fernleigh Castle in Rose Bay home since he purchased it in 1982 for $2.35 million.

Innisfallen was originally a 20-hectare waterfront holding until 1966 when it was subdivided and 75 parcels of land sold off. The following year Willoughby Council bought three blocks of land next to the castle estate to preserve the castle’s heritage value.

In the mid-1980s the historic mansion became the subject of an inquiry called for by then planning minister Bob Carr when the Willis family proposed to convert the castle into apartments and subdivide the block into 12 townhouses.

However, after thousands of objections were lodged, Carr stepped in to rule out the proposed subdivision, prompting a permanent conservation order on the property a few years later and the Willis family to sell it in 1988.

Belle Property Mosman’s Tim Foote has listed it with Sotheby’s International’s Michael Pallier.

There is no guide on the property, but the agents are hoping to set a record for the lower north shore given an estimated $4000 value per square metre, which equates to more than $33 million.

The district high is currently set at $25 million for the Mosman mansion Hopetoun that was bought by Swans chairman Andrew Pridham last year.