Jay Cooke House

The Jay Cooke House is a stone residence on Gibraltar Island in Put-in-Bay, featuring a four-story octagonal tower with a crenellated parapet and rounded-arch openings. The structure combines Gothic Revival elements with solid stone construction and commands attention with its distinctive shape on the island landscape.

Banker Jay Cooke, who financed the Union during the Civil War, built this house in 1865 as a summer retreat. Financial setbacks forced him to sell in 1874, and the property eventually became part of a university research center.

The house carries the name of the banker who commissioned it as a summer residence, and its design reflects the wealth and tastes of 19th-century elites. Visitors can observe the elaborate stonework and distinctive octagonal tower that showcase the architectural preferences of the prosperous class of that era.

The former private residence is now part of Ohio State University's Stone Laboratory and serves as a freshwater research center. The site sits on an island, so a boat journey is needed to reach it, and visiting depends on university activities and access arrangements.

The estate spans 8 acres on Gibraltar Island and offers views of Lake Erie, making it a rare example of a large-scale Victorian summer retreat situated on water. This island location long preserved the site's seclusion and exclusive character.